Add LDAP maintenance task

I've received quite a few support requests where a user has renamed their LDAP server in the configuration file. This causes lots of issues where users are suddenly unable to sign in. It's easy enough to fix through the Rails console, but each time I had to instruct users how to get to the Rails console and what to type. This Rake task takes care of this and updates from old to new provider automatically.

Example: `sudo gitlab-rake gitlab:ldap:rename_provider[ldapmain,ldapcustom]`

cc/ @patricio @balameb Do you think this is useful?

See merge request !2181

[ci skip]

[ci skip]

Move Admin Appearance spinach feature to RSpec

Part of #23036

See merge request !8063

Move buttons to project header

Closes #25692    
Before:   
<img src="/uploads/fb65f1ca8021f1669071a3980e5f8258/Screen_Shot_2016-12-14_at_3.52.19_PM.png" width="800px">
After (with Koding setup):   
<img src="/uploads/236e0103186a1b482c4302aa3a4b94b1/Screen_Shot_2016-12-16_at_10.09.53_AM.png" width="800px">
After (without Koding setup):
<img src="/uploads/04bc8360831c98a4c86d3b11ee24826d/Screen_Shot_2016-12-16_at_10.18.35_AM.png" width="800px">


See merge request !8095

Make CI badge hitboxes better match container

## What does this MR do?

Makes the Pipeline graph badge hitboxes accurately match their containers.
Currently, there's an issue where the badge highlights, as though, it's clickable, but clicking it does nothing:

![before](/uploads/668f841c640bc586044c89bed9f1e1e9/before.gif)

This is due to the `<a>` and `<button>` elements being padded into the parent elements. So, the parent would react to a cursor, but the cursor wouldn't be on the `<a>`/`<button>` yet.

![before-hitbox](/uploads/6ebaaa4be1096fbfc37f8d73da492c7b/before-hitbox.png)

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

Maybe the tests? I kept the style changes as minimal as possible.

## Why was this MR needed?

I was annoyed every time I clicked on a badge that I was _clearly on_ (it highlighted), but nothing happened.
If I found it irritating, perhaps someone else did too.

## Screenshots (if relevant)

How it behaves in the PR:
![finished](/uploads/c26fabe37ccf17f171f40b48522702b2/finished.gif)

## Does this MR meet the acceptance criteria?

- [x] [Changelog entry](https://docs.gitlab.com/ce/development/changelog.html) added
- Tests
  - [x] All builds are passing
- [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 #25547 

See merge request !8156

Move admin broadcast messages spinach feature to RSpec

Part of #23036

See merge request !8067

Backport changes from EE to gl_dropdown.js

REF: https://gitlab.com/gitlab-org/gitlab-ee/merge_requests/977

See merge request !8165

Convert CI YAML variables keys into strings

So that this would be more consistent with the other variables,
which all of them are string based.

Closes #25554

See merge request !8088

Fix import/export merge requests error

When MWBS is set and the MR exported/imported an error gets thrown. We should ignore this so it can succeed as the merge user may no longer exist in the target instance.

Fixes https://gitlab.com/gitlab-org/gitlab-ce/issues/24009 and https://gitlab.com/gitlab-com/support-forum/issues/1345

See merge request !8134

Fix missing service error importing from EE to CE

Ignores services that are missing in the new instance (EE or even a customised instance), to avoid breaking the import.

Fixes https://gitlab.com/gitlab-org/gitlab-ce/issues/23782

See merge request !8144

Fix 500 error for invalid path when visiting blame page

Closes #25761

See merge request !8145

Bump gitlab-shell to 4.1.1

This fixes a compatibility issue with Git 2.11 (#25301):

- [x] gitlab-shell MR: gitlab-org/gitlab-shell!112
- [x] CE MR: !7967
- [x] EE MR: gitlab-org/gitlab-ee!964

See merge request !8143

Signed-off-by: Rémy Coutable <remy@rymai.me>

Move admin labels spinach test to RSpec

Part of #23036

See merge request !8166

Fix duplicated build token problem importing projects

Reset token so duplicated builds do not thrown an error on import

- [x] [Changelog entry](https://docs.gitlab.com/ce/development/changelog.html) 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)
- [ ] [Squashed related commits together](https://git-scm.com/book/en/Git-Tools-Rewriting-History#Squashing-Commits)

Fixes https://gitlab.com/gitlab-org/gitlab-ce/issues/23475

See merge request !8171

Feedback:
https://gitlab.com/gitlab-org/gitlab-ce/merge_requests/8088#note_20235080

with symbols. Feedback:
https://gitlab.com/gitlab-org/gitlab-ce/merge_requests/8088#note_20234245

Improve icons and style for manual build status

## What does this MR do?

This MR changes the CSS class for manual build status badge to make it a little more different than skipped build status badge. It makes it darker.

## Screenshots

![Screen_Shot_2016-12-17_at_13.37.58](/uploads/9628f0e84fdaad82d8833f546f0192a6/Screen_Shot_2016-12-17_at_13.37.58.png)![Screen_Shot_2016-12-17_at_13.31.48](/uploads/fe8e27df0274b9f9ae840110593a298a/Screen_Shot_2016-12-17_at_13.31.48.png)


See merge request !8102

Fix link from doc/development/performance.md to 'Performance Monitoring'

Another link fix!

Fixes link from [doc/development/performance.md](doc/development/performance.md) to 'Gitlab Performance Monitoring'

See merge request !8155

Improve pipeline fixtures

## What does this MR do?
Adds missing fixtures to pipelines.

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

## Why was this MR needed?
To improve testability of https://gitlab.com/gitlab-org/gitlab-ce/issues/24710

## Screenshots (if relevant)

## 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?

See merge request !7792

Feedback:
https://gitlab.com/gitlab-org/gitlab-ce/merge_requests/8088#note_20223109

* master: (327 commits)
  Always use `fixture_file_upload` helper to upload files in tests.
  Add CHANGELOG
  Move admin application spinach test to rspec
  Move admin deploy keys spinach test to rspec
  Fix rubocop failures
  Store mattermost_url in settings
  Improve Mattermost Session specs
  Ensure the session is destroyed
  Improve session tests
  Setup mattermost session
  Fix query in Projects::ProjectMembersController to fetch members
  Improve test for sort dropdown on members page
  Fix sort dropdown alignment
  Undo changes on members search button stylesheet
  Use factories to create project/group membership on specs
  Remove unused id from shared members sort dropdown
  Fix sort functionality on project/group members to return invited users
  Refactor MembersHelper#filter_group_project_member_path
  Remove unnecessary curly braces from sort dropdown partial
  Sort group/project members alphabetically by default
  ...

Fix small typo in CI readme

fix typo

See merge request !8167

Accept environment variables from the `pre-receive` script

## Summary

1. Starting version 2.11, git changed the way the pre-receive flow works.
  - Previously, the new potential objects would be added to the main repo. If the pre-receive passes, the new objects stay in the repo but are linked up. If the pre-receive fails, the new objects stay orphaned in the repo, and are cleaned up during the next `git gc`.
  - In 2.11, the new potential objects are added to a temporary "alternate object directory", that git creates for this purpose. If the pre-receive passes, the objects from the alternate object directory are migrated to the main repo. If the pre-receive fails the alternate object directory is simply deleted.
2. In our workflow, the pre-recieve script (in `gitlab-shell`) calls the
   `/allowed` endpoint, which calls out directly to git to perform
   various checks. These direct calls to git do _not_ have the necessary
   environment variables set which allow access to the "alternate object
   directory" (explained above). Therefore these calls to git are not able to
   access any of the new potential objects to be added during this push.

3. We fix this by accepting the relevant environment variables
   (`GIT_ALTERNATE_OBJECT_DIRECTORIES`, `GIT_OBJECT_DIRECTORY`, and
   `GIT_QUARANTINE_PATH`) on the `/allowed` endpoint, and then include
   these environment variables while calling out to git.

4. This commit includes these environment variables while making the "force
   push" check.

## Issue Numbers

- Closes #25301 (assuming the corresponding `gitlab-shell` MR has been merged in first)
- Corresponding `gitlab-shell` MR: gitlab-org/gitlab-shell!112
- Corresponding EE MR: gitlab-org/gitlab-ee!964

## Tasks

-  [#25301/!7967/!112] Git version 2.11.0 - Can't push to protected branch as master or developer
    - [x]  Investigate
    - [x]  Implementation
        - [x]  `force_push.rb` should use the relevant environment variables
        - [x]  Any other instances of `/allowed` calling out to git directly? 
        - [x]  Verify that the fix works over SSH as well
        - [x]  Can we trim the number of env variables? Do we need all 3?
        - [x]  Whitelist variables. Server shouldn't pass through _any_ env variable passed in
        - [x]  Any security implications?
        - [x]  Check for force push return code
        - [x]  Shouldn't be able to opt-out from the force push check by passing an env variable
    - [x]  Tests
        - [x]  CE
            - [x]  Added
            - [x]  Passing
        - [x]  Shell
            - [x]  Added
            - [x]  Passing
    - [x]  Meta
        - [x]  CHANGELOG entry created
        - [x]  Branch has no merge conflicts with `master`
        - [x]  Squashed related commits together
        - [x]  EE merge request
    - [x]  Review
        - [x]  Endboss
    - [ ]  Follow-up
        - [x]  Make sure EE is working as expected
        - [x]  [CE] Gitlab changes without gitlab-shell changes shouldn't raise any exceptions
        - [x]  [CE] Gitlab-shell changes without gitlab changes shouldn't raise any exceptions
        - [x]  [EE] Gitlab changes without gitlab-shell changes shouldn't raise any exceptions
        - [x]  [EE] Gitlab-shell changes without gitlab changes shouldn't raise any exceptions
    - [ ]  Wait for merge
        - [ ]  CE
        - [ ]  EE
        - [x]  Shell


See merge request !7967

https://gitlab.com/gitlab-org/gitlab-ce/issues/23036

Allow to use Dockerfile templates

See merge request !7247

Move admin application spinach test to RSpec

Part of #23036

See merge request !8140