Allow slack service to send messages on different channels

closes #8110 

## Allow slack service to send messages on different channels  

![new_slack_service](/uploads/87de0bd6b02a4f7853358676b5e74dff/new_slack_service.png)

## 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)
- [x] API support added
- Tests
  - [x] Added for this feature/bug
  - [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 you do - rebase it please)
- [x] [Squashed related commits together](https://git-scm.com/book/en/Git-Tools-Rewriting-History#Squashing-Commits)

See merge request !5124

Fix two small problems on how we handle manual actions

## What does this MR do?
Fixes two small problems in how we handle manual actions:
- On environments page we show a `Play` for the same action that is lately deployed, we should show other actions only
- When we process a pipeline that have only a manual action in a stage, the pipeline will stop being processed.

- Tests
  - [ ] Added for this feature/bug
  - [ ] All builds are passing
- [ ] 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 !5366

Resolve "gitlab:setup rake task fails on 8.8.1 source install"

_Originally opened at !4788 by @rickettm._

- - -

## What does this MR do?

Fix bug #15344, so that the limit parameter that is already passed in to the print_users function is actually used, rather than using a hardcoded value.

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

No, it is a trivial change.

## Why was this MR needed?

This bug causes 100 LDAP users to be displayed even when a different limit is given, which can be annoying.

## What are the relevant issue numbers?

Fixes #15344.

## Does this MR meet the acceptance criteria?

- [x] [CHANGELOG](https://gitlab.com/gitlab-org/gitlab-ce/blob/master/CHANGELOG) entry added
- [x] Branch has no merge conflicts with `master` (if you do - rebase it please)
- [x] [Squashed related commits together](https://git-scm.com/book/en/Git-Tools-Rewriting-History#Squashing-Commits)

See merge request !5364

Remove icons from explore nav

## What does this MR do?
Removes icons from explore `nav/_explore`

## Why was this MR needed?
To match signed-in nav

## Screenshots (if relevant)
Before:   
![Screen_Shot_2016-07-20_at_6.39.01_AM](/uploads/9ccc11d151e37a0ef2fab681ccc07efa/Screen_Shot_2016-07-20_at_6.39.01_AM.png)

After:   
![Screen_Shot_2016-07-20_at_6.43.15_AM](/uploads/ae058b19cc3c887bccf6c221ac58cfc2/Screen_Shot_2016-07-20_at_6.43.15_AM.png)


See merge request !5362

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

Apply diff view cookie on compare

## What does this MR do?

Correctly respects the code view changing when comparing 2 refs.

## What are the relevant issue numbers?

Closes #19573 

## Screenshots (if relevant)

![Screen_Shot_2016-07-07_at_12.38.07](/uploads/b6da78cc2bbc2c79dbe8292037176c1a/Screen_Shot_2016-07-07_at_12.38.07.png)

![Screen_Shot_2016-07-07_at_12.38.17](/uploads/977f8b697c65bdb1701db11a39287ac6/Screen_Shot_2016-07-07_at_12.38.17.png)

See merge request !5135

Resolve "Move Build badges settings to Builds page (or Builds settings)"

## What does this MR do?
Removes pipeline settings section from project settings & creates a new pipelines settings page    
Adds builds badge to pipelines settings page & removes badge page

## Are there points in the code the reviewer needs to double check?
All Rails updates -> particularly `builds_controller.rb` and `routes`   
Spacing needs to be updated across all settings pages and will be in a separate MR (https://gitlab.com/gitlab-org/gitlab-ce/issues/19827)

## What are the relevant issue numbers?
Closes #15343    
Part of #18920 

## Screenshots (if relevant)
![Screen_Shot_2016-07-19_at_5.47.29_AM](/uploads/48e6d203de4cbe0b697280128695d980/Screen_Shot_2016-07-19_at_5.47.29_AM.png)
![Screen_Shot_2016-07-14_at_9.25.13_AM](/uploads/59118440f3e7bb903f44260abb119376/Screen_Shot_2016-07-14_at_9.25.13_AM.png)

See merge request !5244

Fix Issue 19641 (new snippets style bug)

## What does this MR do?
Fixes Issue 19641 (new snippets style bug)

## Are there points in the code the reviewer needs to double check?
Shouldn't be

## Why was this MR needed?
Requested in issue 19641 by Fatih Acet https://gitlab.com/gitlab-org/gitlab-ce/issues/19641

## What are the relevant issue numbers?
19641

## Screenshots (if relevant)
![Screenshot_2016-07-09_13.25.39](/uploads/8ead7ea8f4aae7ccaa4d2ddc495b6fe3/Screenshot_2016-07-09_13.25.39.png)
## Does this MR meet the acceptance criteria?
Yes

- [ x] [CHANGELOG](https://gitlab.com/gitlab-org/gitlab-ce/blob/master/CHANGELOG) entry added
- [ NA] [Documentation created/updated](https://gitlab.com/gitlab-org/gitlab-ce/blob/master/doc/development/doc_styleguide.md)
- [ NA] API support added
- Tests
  - [NA ] Added for this feature/bug
  - [ 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 you do - rebase it please)
- [ x] [Squashed related commits together](https://git-scm.com/book/en/Git-Tools-Rewriting-History#Squashing-Commits)

See merge request !5170

Allow to disable user request access to groups/projects

fixes #18585 

![projects](/uploads/9f381e77ffbcd2ecdbabdb8b201b95e4/projects.png)  

![namespaces](/uploads/4b8d39c80576b499118373f0a221882c/namespaces.png)

## 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
- [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 you do - rebase it please)
- [x] [Squashed related commits together](https://git-scm.com/book/en/Git-Tools-Rewriting-History#Squashing-Commits)

See merge request !5286

Add predefined CI variables to GitLab

## What does this MR do?
This adds predefined CI variables to GitLab for container registry, pipelines, project name, etc. It also makes sure that all currently documented variables are send from GitLab. This is added to follow up on this proposal: https://gitlab.com/gitlab-org/gitlab-ci-multi-runner/issues/185#note_11844286. To migrate almost all variables out of Runner to GitLab to simplify adding a new of variables without the need for changing the GitLab Runner.

## Why was this MR needed?
Our CI variables miss a lot of crucial information that should be easily accessible. This tries to fill this gap.

## What are the relevant issue numbers?
Fixes https://gitlab.com/gitlab-org/gitlab-ci-multi-runner/issues/185, https://gitlab.com/gitlab-org/gitlab-ce/issues/18164, https://gitlab.com/gitlab-org/gitlab-ce/issues/18075.

## Does this MR meet the acceptance criteria?

- [ ] [CHANGELOG](https://gitlab.com/gitlab-org/gitlab-ce/blob/master/CHANGELOG) entry 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 [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 !4826

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

Updated fork page UI

## What does this MR do?

Updates fork page to new UI.

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

😕 

## Why was this MR needed?

'coz new forks page looks awesome, that's why!

## What are the relevant issue numbers?

Closes #17810.

## Screenshots (if relevant)

![Screen_Shot_2016-07-07_at_03.43.45](/uploads/d4be046d1a6b043f3691633b7ec396c6/Screen_Shot_2016-07-07_at_03.43.45.png)

[youtube video](https://youtu.be/YpXPCxWGCnY)

## Does this MR meet the acceptance criteria?

- [ ] [CHANGELOG](https://gitlab.com/gitlab-org/gitlab-ce/blob/master/CHANGELOG) entry 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
- [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 you do - rebase it please)
- [ ] [Squashed related commits together](https://git-scm.com/book/en/Git-Tools-Rewriting-History#Squashing-Commits)

See merge request !5007

Replace namespace-specific application.js files with namespace-bundle.js files.

Following up on the per-page JavaScript improvements, I wanted to replace the use of `application.js` with `namespace-bundle.js` to prevent confusion when downloading more than one application.js file.

This is pretty much just for the sake of clarity.

cc: @alfredo1 

See merge request !5221

Log cron_jobs configuration instead of raising exception

## What does this MR do?

Log cron_jobs configuration errors and remove invalid key <-> values from the configuration hash instead of raising an exception.
This has been discussed at #20010.

Fixes #20010

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

## Why was this MR needed?

Original implementation !5318, introduced a regression with our docker packaging: #20010.

## What are the relevant issue numbers?

* #20010 
* #18378

## Does this MR meet the acceptance criteria?

- [ ] [CHANGELOG](https://gitlab.com/gitlab-org/gitlab-ce/blob/master/CHANGELOG) entry 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 [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 !5360

speed up ExternalWikiService#get_project_wiki_path

## What does this MR do?

Speed up ExternalWikiHelper#get_project_wiki_path

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

## Why was this MR needed?

See issue #19886 

## What are the relevant issue numbers?

#19886 

## Screenshots (if relevant)

## Does this MR meet the acceptance criteria?

- [x] [CHANGELOG](https://gitlab.com/gitlab-org/gitlab-ce/blob/master/CHANGELOG) entry 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 [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 !5305

Fix migration corrupting import data for old version upgrades

Fixes https://gitlab.com/gitlab-org/gitlab-ce/issues/19073

Not a fan of changing old migrations but this will prevent issues from upgrading GitLab version 8.6 or older to 8.10

More details of the issue on https://gitlab.com/gitlab-org/gitlab-ce/issues/19073#note_13190450

See merge request !5358

Merge branch '20003-newnoteworker-failing-repeatedly-with-argumenterror-wrong-number-of-arguments' into 'master'

Ensure to_json methods take optional argument

If only Ruby had static checking for interfaces like this 😀 

Closes #20003.

See merge request !5359

Expire tags/branches repo cache before delete a repository

## What does this MR do?

Explicitly expire tag and branch cache data before deleting a repository. Those keys don't depend on git data when they are expired

## Why was this MR needed?

To solve an existing problem https://sentry.gitlap.com/gitlab/gitlabcom/issues/8756/

## What are the relevant issue numbers?

Closes #20011

## Screenshots (if relevant)

## Does this MR meet the acceptance criteria?

- [x] [CHANGELOG](https://gitlab.com/gitlab-org/gitlab-ce/blob/master/CHANGELOG) entry added
- ~~[ ] [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 [style guides](https://gitlab.com/gitlab-org/gitlab-ce/blob/master/CONTRIBUTING.md#style-guides)
- [x] Branch has no merge conflicts with `master` (if you do - rebase it please)
- [x] [Squashed related commits together](https://git-scm.com/book/en/Git-Tools-Rewriting-History#Squashing-Commits)

See merge request !5356

Replace parse_boolean with to_boolean

## What does this MR do?

Replaces `.parse_boolean` with the new `.to_boolean` as we talked in the other MR.

## 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

  ~~- [ ] Added for this feature/bug~~
  - [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 you do - rebase it please)
- [x] [Squashed related commits together](https://git-scm.com/book/en/Git-Tools-Rewriting-History#Squashing-Commits)

See merge request !5355

Fix the Sentry spam from CSP violations by disabling it.

## What does this MR do?

Leaves CSP enabled, but without a reporting endpoint for now. This was causing a huge amount of useless errors in our Sentry instance.

cc: @stanhu 

See merge request !5354