Improve bulk assignment

This MR improves current implementation of Label dropdown when used for bulk assignment on issuable pages (/:namespace/:project/issues, /:namespace/:project/merge_requests)

Previously this dropdown relied on `<input>` tags to get its active items and also to calculate items with indeterminate state.

Relying on `<input>` tags is not enough when we want to set/get multiple states on a dropdown.

For this case we want to get/set:

- Marked items 
- Unmarked items that were initially marked
- Unmarked items that were initially indeterminate
- Items with indeterminate state.

This MR makes the Label dropdown to save its own state as `data` so it will be easy to get and set whatever state we want no matter if the dropdown is filtering which is the issue that I initially wanted to solve as you can see in the following gif.

**Before** 
![2016-12-07_11.44.48](/uploads/cb697161b8b39cdee72fdbb95a531100/2016-12-07_11.44.48.gif)

**After**
![2016-12-07_11.32.43](/uploads/338255a302de0dd1367474f33232d2a3/2016-12-07_11.32.43.gif)

As you can see in the first gif the `bug` label is removed from the selected issues but the `enhancement` label should set but the `critical` should be kept. This is fixed on the next gif.

Fixes #24877

See merge request !7765

25617 Fix placeholder color of todo filters

## What does this MR do?
Fixes color of placeholder text on todo filters

## Screenshots (if relevant)

![Screen_Shot_2016-12-14_at_1.42.02_PM](/uploads/7ceec3c8fff47825384835bcfb38d77c/Screen_Shot_2016-12-14_at_1.42.02_PM.png)

## Does this MR meet the acceptance criteria?

- [ ] [Changelog entry](https://docs.gitlab.com/ce/development/changelog.html) added
- [ ] [Documentation created/updated](https://gitlab.com/gitlab-org/gitlab-ce/blob/master/doc/development/doc_styleguide.md)
- [ ] API support added
- Tests
  - [ ] Added for this feature/bug
  - [ ] All builds are passing
- [ ] Conform by the [merge request performance guides](http://docs.gitlab.com/ce/development/merge_request_performance_guidelines.html)
- [ ] Conform by the [style guides](https://gitlab.com/gitlab-org/gitlab-ce/blob/master/CONTRIBUTING.md#style-guides)
- [ ] Branch has no merge conflicts with `master` (if it does - rebase it please)
- [ ] [Squashed related commits together](https://git-scm.com/book/en/Git-Tools-Rewriting-History#Squashing-Commits)

## What are the relevant issue numbers?
Closes #25617

See merge request !8094

24824 Add focus state to dropdowns

## What does this MR do?
Adds focus state to dropdown items to increase accessibility. 

## Screenshots (if relevant)

![Screen_Shot_2016-12-01_at_2.47.13_PM](/uploads/d0d2c17dde61314c86155268815091f6/Screen_Shot_2016-12-01_at_2.47.13_PM.png)

## Does this MR meet the acceptance criteria?

- [ ] [Changelog entry](https://docs.gitlab.com/ce/development/changelog.html) added
- [ ] [Documentation created/updated](https://gitlab.com/gitlab-org/gitlab-ce/blob/master/doc/development/doc_styleguide.md)
- [ ] API support added
- Tests
  - [ ] Added for this feature/bug
  - [ ] All builds are passing
- [ ] Conform by the [merge request performance guides](http://docs.gitlab.com/ce/development/merge_request_performance_guidelines.html)
- [ ] Conform by the [style guides](https://gitlab.com/gitlab-org/gitlab-ce/blob/master/CONTRIBUTING.md#style-guides)
- [ ] Branch has no merge conflicts with `master` (if it does - rebase it please)
- [ ] [Squashed related commits together](https://git-scm.com/book/en/Git-Tools-Rewriting-History#Squashing-Commits)

## What are the relevant issue numbers?
Closes #24824

See merge request !7885

Show commit status from latest pipeline

Show commit status from latest pipeline rather than compound status from all pipelines.

Closes #20560

See merge request !7333

Remove unnecessary commits order message

Remove unnecessary message. User should expect that commits are listed in reverse chronological order. Even if they are not initially clear, glancing quickly through the list informs them right away. No point in drawing unnecessary attention to extra information that is not main content. The other tabs also have lists in chronological or reverse chronological order. But there's nothing there to explain in which direction.

### Existing
<img src="/uploads/d5592533c60186a7a53af5d6d010fa56/Screen_Shot_2016-12-09_at_12.38.25_AM.png" height="200px" />

### After change
<img src="/uploads/facc800496d27f1ee33e0d48d339b2f3/Screen_Shot_2016-12-09_at_12.37.36_AM.png" height="200px" />

See merge request !8004

Fixed GFM autocomplete to disallow non-word characters in string

## What does this MR do?

Disallows GFM autocomplete working when a non-word character is enter in the middle of the string.

## Screenshots (if relevant)

![Screen_Shot_2016-12-12_at_09.47.46](/uploads/aa6463a57b97c103c69eab6bb1d80540/Screen_Shot_2016-12-12_at_09.47.46.png)

## What are the relevant issue numbers?

Closes #25540

See merge request !8035

added go back anchor on error pages

## What does this MR do?

adds go back anchor on error pages

## Are there points in the code the reviewer needs to double check?
-

## Why was this MR needed?

requested per https://gitlab.com/gitlab-org/gitlab-ce/issues/25534

## Screenshots (if relevant)

![image](/uploads/894c513e7a058deb0124b5152dc11e28/image.png)

## Does this MR meet the acceptance criteria?

- [x] [Changelog entry](https://docs.gitlab.com/ce/development/changelog.html) added
- [ ] [Documentation created/updated](https://gitlab.com/gitlab-org/gitlab-ce/blob/master/doc/development/doc_styleguide.md)
- [ ] API support added
- Tests
  - [ ] Added for this feature/bug
  - [ ] All builds are passing
- [ ] Conform by the [merge request performance guides](http://docs.gitlab.com/ce/development/merge_request_performance_guidelines.html)
- [ ] Conform by the [style guides](https://gitlab.com/gitlab-org/gitlab-ce/blob/master/CONTRIBUTING.md#style-guides)
- [ ] Branch has no merge conflicts with `master` (if it does - rebase it please)
- [ ] [Squashed related commits together](https://git-scm.com/book/en/Git-Tools-Rewriting-History#Squashing-Commits)

## What are the relevant issue numbers?

Closes #25534

See merge request !8087

Add Object.assign polyfill

Because PhantomJS

See merge request !8090

Move admin active tab spinach tests to RSpec

See merge request !8037

Use build instead create in group spec

See merge request !8068

Fixed file template dropdown for the "New File" editor for smaller/zoomed screens

## What does this MR do?

Fixes the dropdown issue on zoomed/smaller screens

## Are there points in the code the reviewer needs to double check?

Until what point do we consider not supporting a certain screen size / zoom level

## Why was this MR needed?

To fix the dropdown position when zooming in on the screen

## Screenshots (if relevant)

Zoom levels

**100% Zoom**
![100_](/uploads/b13c6c48d4ca99b119d45975280cd16f/100_.png)

**175% Zoom**
![175_](/uploads/ef25dffbf85d0859bc57c875914ffc7a/175_.png)

**200% Zoom**
![200_](/uploads/6ff7709f42304d51ef29a173efa5540d/200_.png)

**300% Zoom**
![300_](/uploads/7e57528582a09355354bbbfc26aa64a4/300_.png)

## Does this MR meet the acceptance criteria?

- [X] [Changelog entry](https://docs.gitlab.com/ce/development/changelog.html) added
- [ ] [Documentation created/updated](https://gitlab.com/gitlab-org/gitlab-ce/blob/master/doc/development/doc_styleguide.md)
- [ ] API support added
- Tests
  - [ ] Added for this feature/bug
  - [X] All builds are passing
- [X] Conform by the [merge request performance guides](http://docs.gitlab.com/ce/development/merge_request_performance_guidelines.html)
- [X] Conform by the [style guides](https://gitlab.com/gitlab-org/gitlab-ce/blob/master/CONTRIBUTING.md#style-guides)
- [X] Branch has no merge conflicts with `master` (if it does - rebase it please)
- [X] [Squashed related commits together](https://git-scm.com/book/en/Git-Tools-Rewriting-History#Squashing-Commits)

## What are the relevant issue numbers?

Closes #23962 

## Affected pages for the modified css-classes

`./app/assets/stylesheets/pages/editor.scss:  .gitignore-selector,
./app/assets/stylesheets/pages/editor.scss:  .license-selector,
./app/assets/stylesheets/pages/editor.scss:  .gitlab-ci-yml-selector {
./app/views/projects/blob/_editor.html.haml:      .gitlab-ci-yml-selector.js-gitlab-ci-yml-selector-wrap.hidden
./app/assets/stylesheets/pages/editor.scss:  .new-file-name {
./app/views/projects/blob/_editor.html.haml:        required: true, class: 'form-control new-file-name' `

See merge request !7807

Add a slug to environments

## What does this MR do?

Adds a `slug` field to the `environments` table, populating existing rows and ensuring that new rows will get an entry.

Cleaning examples:

* `review/foo`  => `review-foo-5gghdf`
* `review-foo` => `review-foo`
* `1-foo` => `env-1-foo-e2hx12`
* `production` => `production`
* `Production` => `production-f8ddlz`

## Are there points in the code the reviewer needs to double check?

This migration requires downtime. I don't see a way to avoid it.

## Why was this MR needed?

External services often have more restrictive rules on naming than those enforced for `environments.name`. In particular, forward slashes and names longer than 24 characters causes problems on OpenShift. `slug` is designed to be an acceptable alternative to `name` in these situations. Since forward slashes are a documented part of environment names, to set environment types, we need an envionmnent slug, not just a slug for the branch name.

## Does this MR meet the acceptance criteria?

- [x] [Changelog entry](https://docs.gitlab.com/ce/development/changelog.html) added
- [x] [Documentation created/updated](https://gitlab.com/gitlab-org/gitlab-ce/blob/master/doc/development/doc_styleguide.md)
- [X] API support added
- Tests
  - [X] Added for this feature/bug
  - [x] All builds are passing
- [X] Conform by the [merge request performance guides](http://docs.gitlab.com/ce/development/merge_request_performance_guidelines.html)
- [X] Conform by the [style guides](https://gitlab.com/gitlab-org/gitlab-ce/blob/master/CONTRIBUTING.md#style-guides)
- [X] Branch has no merge conflicts with `master` (if it does - rebase it please)
- [X] [Squashed related commits together](https://git-scm.com/book/en/Git-Tools-Rewriting-History#Squashing-Commits)

## What are the relevant issue numbers?

Part of #22864

See merge request !7983

Filter `incoming_email_token` and `runners_token` parameters

Closes https://dev.gitlab.org/gitlab/gitlabhq/issues/2676

See merge request !2045

Issue#visible_to_user moved to IssuesFinder

Fixes https://gitlab.com/gitlab-org/gitlab-ce/issues/24637.

See merge request !2039

Fix missing Note access checks in by moving Note#search to updated NoteFinder

Split from !2024 to partially solve https://gitlab.com/gitlab-org/gitlab-ce/issues/23867

## Which fixes are in this MR?

⚠ - Potentially untested  
💣 - No test coverage  
🚥 - Test coverage of some sort exists (a test failed when error raised)  
🚦 - Test coverage of return value (a test failed when nil used)  
✅ - Permissions check tested

### Note lookup without access check

- [x] ✅ app/finders/notes_finder.rb:13 :download_code check
- [x] ✅ app/finders/notes_finder.rb:19 `SnippetsFinder`
- [x] ✅ app/models/note.rb:121 [`Issue#visible_to_user`]
- [x] ✅ lib/gitlab/project_search_results.rb:113
  - This is the only use of `app/models/note.rb:121` above, but importantly has no access checks at all. This means it leaks MR comments and snippets when those features are `team-only` in addition to the issue comments which would be fixed by `app/models/note.rb:121`.
  - It is only called from SearchController where `can?(current_user, :download_code, @project)` is checked, so commit comments are not leaked.

### Previous discussions
- [x] https://dev.gitlab.org/gitlab/gitlabhq/merge_requests/2024/diffs#b915c5267a63628b0bafd23d37792ae73ceae272_13_13 `: download_code` check on commit
- [x] https://dev.gitlab.org/gitlab/gitlabhq/merge_requests/2024/diffs#b915c5267a63628b0bafd23d37792ae73ceae272_19_19 `SnippetsFinder` should be used
  - `SnippetsFinder` should check if the snippets feature is enabled -> https://gitlab.com/gitlab-org/gitlab-ce/issues/25223

###  Acceptance criteria met?
- [x] Tests added for new code
- [x] TODO comments removed
- [x] Squashed and removed skipped tests
- [x] Changelog entry
- [ ] State Gitlab versions affected and issue severity in description
- [ ] Create technical debt issue for NotesFinder.
  - Either split into `NotesFinder::ForTarget` and `NotesFinder::Search` or consider object per notable type such as `NotesFinder::OnIssue`. For the first option could create `NotesFinder::Base` which is either inherited from or which can be included in the other two.
  - Avoid case statement anti-pattern in this finder with use of `NotesFinder::OnCommit` etc. Consider something on the finder for this? `Model.finder(user, project)`
  - Move `inc_author` to the controller, and implement `related_notes` to replace `non_diff_notes`/`mr_and_commit_notes`

See merge request !2035

Document `repocheck.log` in logs docs

Closes https://gitlab.com/gitlab-org/gitlab-ce/issues/25622

See merge request !8105

[ci skip]

[ci skip]

Render math in Asciidoc and Markdown with KaTeX using code blocks

Closes #13690 and #13180

See merge request !8003

Remove duplicated parameter description

## What does this MR do?

Remove a duplicated parameter entry in the projects API

See merge request !8099

Replace Rack::Multipart with gitlab-workhorse based system

See merge request !5867

Allow users to seed the initial runner registration token using an environment variable

## What does this MR do?
Allow users to seed the initial runner registration token using an environment variable

## Are there points in the code the reviewer needs to double check?

- Naming, do we want to make sure we are clear it's the 'registration' token. Like GITLAB_RUNNER_REGISTRATION_TOKEN vs what I have now, GITLAB_RUNNER_TOKEN
- Not sure we've tested a seed fixture before, I just made up a directory structure for the test

## Why was this MR needed?

At the moment I want to use this in our idea to production demo:  https://gitlab.com/gitlab-org/gitlab-ce/issues/22190

This is useful for when runner is bundled with gitlab, like in a kubernetes stack, and we want the runner to be able to register with gitlab as soon as they both come up.

## Does this MR meet the acceptance criteria?

- [x] [CHANGELOG](https://gitlab.com/gitlab-org/gitlab-ce/blob/master/CHANGELOG) entry added
- [x] [Documentation created/updated](https://gitlab.com/gitlab-org/gitlab-ce/blob/master/doc/development/doc_styleguide.md)
- [ ] API support added
- Tests
  - [x] Added for this feature/bug
  - [x] All builds are passing
- [ ] Conform by the [merge request performance guides](http://docs.gitlab.com/ce/development/merge_request_performance_guidelines.html)
- [ ] Conform by the [style guides](https://gitlab.com/gitlab-org/gitlab-ce/blob/master/CONTRIBUTING.md#style-guides)
- [ ] Branch has no merge conflicts with `master` (if you do - rebase it please)
- [ ] [Squashed related commits together](https://git-scm.com/book/en/Git-Tools-Rewriting-History#Squashing-Commits)

See merge request !6642

Fix Slack pipeline message by API

Pipelines triggered from API don't have a corresponding
user, so we show that it's from API, same as from the
web UI

Closes #25609

See merge request !8059

Introduce $CI_BUILD_REF_SLUG

## What does this MR do?

Adds `$CI_BUILD_REF_SLUG` to the variables exposed to the runner. This is based on `$CI_BUILD_REF_NAME` but lowercased, shortened to 63 bytes maximum, and with characters invalid in URLs and domain names replaced with `-`. 

## Are there points in the code the reviewer needs to double check?

Slugs don't have a uniqueness guarantee. !7983 introduces an environment name slug which *is* unique, so I'm not as exercised about this as I was.

Should the slug be published in the API? It's available through the `variables` endpoint, but perhaps it should be part of `GET /project/:id/builds` ?

I've called it `ref_slug` rather than just `slug` as there are number of possibilities for slugification in a build (unlike an environment, where only the name makes sense to slugify).

## Why was this MR needed?

`$CI_BUILD_REF_NAME` is not suited for URLs and domain names, given the list of valid characters in a git ref. 

## Screenshots (if relevant)

## Does this MR meet the acceptance criteria?

- [x] [Changelog entry](https://docs.gitlab.com/ce/development/changelog.html) added
- [X] [Documentation created/updated](https://gitlab.com/gitlab-org/gitlab-ce/blob/master/doc/development/doc_styleguide.md)
- [ ] API support added
- Tests
  - [X] Added for this feature/bug
  - [x] All builds are passing
- [X] Conform by the [merge request performance guides](http://docs.gitlab.com/ce/development/merge_request_performance_guidelines.html)
- [X] Conform by the [style guides](https://gitlab.com/gitlab-org/gitlab-ce/blob/master/CONTRIBUTING.md#style-guides)
- [X] Branch has no merge conflicts with `master` (if it does - rebase it please)
- [X] [Squashed related commits together](https://git-scm.com/book/en/Git-Tools-Rewriting-History#Squashing-Commits)

## What are the relevant issue numbers?

Closes #22849

See merge request !8072

https://gitlab.com/gitlab-org/gitlab-ce/merge_requests/7333#note_20058993

https://gitlab.com/gitlab-org/gitlab-ce/merge_requests/7333#note_20059060

https://gitlab.com/gitlab-org/gitlab-ce/merge_requests/7333#note_20059357

Feedback:
https://gitlab.com/gitlab-org/gitlab-ce/merge_requests/7333#note_20058743

Feedback:

https://gitlab.com/gitlab-org/gitlab-ce/merge_requests/7333#note_20059124

https://gitlab.com/gitlab-org/gitlab-ce/merge_requests/7333#note_20059187

https://gitlab.com/gitlab-org/gitlab-ce/merge_requests/7333#note_20059322

https://gitlab.com/gitlab-org/gitlab-ce/merge_requests/7333#note_20058857

Fix transient failure on AnalyticsBuildEntity

AnalyticsBuildEntity uses `Time.now` to calculate durations, and on slow running builds could fail this spec. Mocking with `Timecop` should be sufficient to fix this.

Fixes https://gitlab.com/gitlab-org/gitlab-ce/issues/25500

See merge request !8082

Delete more page specific css

* Moves emojis and icons into `framework`
* Comments out unused bootstrap imports (we can remove them entirely later)

See merge request !7961