Cache Participable#participants in instance variable

See merge request !4803

GitLab CI Yaml template dropdown

## What does this MR do?
Make it possible to select a dropdown for an easy start with GitLab CI.

## What are the relevant issue numbers?
Closes #17521

## TODO
- [ ] Backend
  - [x] CHANGELOG item
  - [x] Fix rubocop failure
  - [x] API Support
  - [x] New tests
  - [x] Add disclaimer to the top of the gitlab-ci.yml
- [ ] Frontend
  - [x] New tests

See merge request !4411

Make it possible to lock runner on a specific project

Make it possible to lock runner on a specific project.

![Screen_Shot_2016-06-20_at_4.03.08_PM](/uploads/186378643a20106ff0b67b6fd8bd7f28/Screen_Shot_2016-06-20_at_4.03.08_PM.png)

----

![Screen_Shot_2016-06-20_at_9.54.52_PM](/uploads/c479abdffaf19f383bb6b5a42bdd6cc3/Screen_Shot_2016-06-20_at_9.54.52_PM.png)

----

![Screen_Shot_2016-06-20_at_9.56.26_PM](/uploads/6ad838679b0c28a1fe2e20e9224387ea/Screen_Shot_2016-06-20_at_9.56.26_PM.png)

Closes #3407

See merge request !4093

Remove calls to Rugged::BranchCollection#each from extracts_path before_action

See merge request !4802

Remove explicit Gitlab::Metrics.action assignments, are already automatic.

See merge request !4731

https://gitlab.com/gitlab-org/gitlab-ce/merge_requests/4093#note_12594802

Document email on push service

Addresses https://gitlab.com/gitlab-org/gitlab-ee/issues/80

See merge request !4698

Make lists on notes to look the same in preview mode and published

## What does this MR do?
Makes list styles on notes to be the same. Previously the styles weren't shared.

## Screenshots (if relevant)
**Previous**

![label-style-old](/uploads/f121fe99e9255cf0d75185185f51fec2/label-style-old.gif)

**After**

![label-style](/uploads/23febf41aaf8796d250a662fa6dc15d2/label-style.gif)

See merge request !4765

Stop edit note up key shortcut conflicting with native shortcuts

## What does this MR do?

Restricts edit note shortcut to only the `up` button, if modifier keys are used it will not fire the shortcut.

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

Ney.

## Why was this MR needed?

UX

## What are the relevant issue numbers?

Closes #18113.

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

See merge request !4761

Corrected top search area css media query param

## What does this MR do?

Corrects top search area css media query so it switches styles at the correct screen size.

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

It's a regression so likely

## Why was this MR needed?

UX

## What are the relevant issue numbers?

Closes #18490. (This stops the search bar dropping into its own row until it needs to be 100% column stacked anyway)

## Screenshots (if relevant)

![Screen_Shot_2016-06-17_at_17.45.38](/uploads/2278e2cdb1c2de14fc098e30fd5328d8/Screen_Shot_2016-06-17_at_17.45.38.png)

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

See merge request !4756

Documented the up key shortcut

## What does this MR do?

Documents the `up` key edit note shortcut in the `/help/_shortcuts.html.haml` help pane and the `/doc/workflow/shortcuts.png` screenshot.

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

The issue and MR shortcuts should be merged, they're the same? Shall I open an issue or include here?

This panel also need to be a little more responsive. Shall I open an issue or include here?

Additionally, I have some conflicts regarding the screenshot. This screenshot also needs to update for !4570.

## Why was this MR needed?

Everyone should know about this awesome shortcut.

## What are the relevant issue numbers?

Closes #18114.

## Screenshots (if relevant)

View the [updated screenshot](https://gitlab.com/gitlab-org/gitlab-ce/blob/e7221ad66efeb0f7d263ead7ed523d194243fb09/doc/workflow/shortcuts.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
  - [ ] 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)
- [x] [Squashed related commits together](https://git-scm.com/book/en/Git-Tools-Rewriting-History#Squashing-Commits)

See merge request !4758

Fixed merge on success widget buttons on mobile

## What does this MR do?

Fixes 'merge on success' widget buttons on mobile as they were stacked with 100% width before when it is a button group with a small dropdown button.

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

Ney

## Why was this MR needed?

mobile UX

## What are the relevant issue numbers?

Closes #18610.

## Screenshots (if relevant)

![Screen_Shot_2016-06-17_at_03.09.36](/uploads/b662e1b7ad683cd89f1233a859caccb2/Screen_Shot_2016-06-17_at_03.09.36.png)

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

See merge request !4726

Fixes font weight of commit id on view file button

## What does this MR do?

Changes the weight to normal. With the new commit UI - this had turned bold and didn't match the designs.

Should it also be our normal font family? According to designs it is - but everywhere else there is a commit ID it has the monospace font.

## Screenshots (if relevant)

![Screen_Shot_2016-06-16_at_17.25.33](/uploads/bb76d576c10be65172d5f4e9790ca766/Screen_Shot_2016-06-16_at_17.25.33.png)

See merge request !4713

Fix regressions in the design of the project statistics bar.

## What does this MR do?

Improves the design of the empty Changelog, Contribution guide, and License items in the project statistics bar.

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

Don't think so, maybe that the `project-stats` class isn't used anywhere else (a grep suggests it's not)

## Why was this MR needed?

Because the empty state of the repository didn't look as good anymore.

## What are the relevant issue numbers?
#18734

## Screenshots (if relevant)

Before:

![Screen_Shot_2016-06-16_at_12.15.22_PM](/uploads/a5c27d696af186346a2298071c90ba2d/Screen_Shot_2016-06-16_at_12.15.22_PM.png)

After:

![Screen_Shot_2016-06-16_at_12.59.38_PM](/uploads/8719d3ee507affd4ce7ea479a5422908/Screen_Shot_2016-06-16_at_12.59.38_PM.png)

See merge request !4717

This commit builds on the groundwork in
ee008e300b1ec0abcc90e6a30816ec0754cea0dd, which refactored the backend
so the same code could be used for new dropdowns. In this commit its
used for templates for the `.gitlab-ci.yml` files.

Add borders to images in issues, MRs, and Help.

## What does this MR do?

Adds a gray border around images in Issues, MRs, and Help pages.

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

That this doesn't effect other elements or pages that it shouldn't.

## Why was this MR needed?

It was hard to differentiate between the actual interface and screenshots of it.

## What are the relevant issue numbers?

Fixes #18578 

## Screenshots (if relevant)

### Issues/MRs

Before:

![Screen_Shot_2016-06-14_at_12.22.08_PM](/uploads/00a242a5b4a09b5308f02e6e498862a8/Screen_Shot_2016-06-14_at_12.22.08_PM.png)

After:

![Screen_Shot_2016-06-14_at_12.22.30_PM](/uploads/8fc9fc1c561d788b050e48373449771b/Screen_Shot_2016-06-14_at_12.22.30_PM.png)

![Screen_Shot_2016-06-14_at_12.22.39_PM](/uploads/36c91b2f2ce1eeb77f1646415baea14d/Screen_Shot_2016-06-14_at_12.22.39_PM.png)

### Help

Before:

![Screen_Shot_2016-06-14_at_11.58.54_AM](/uploads/7620491ca338064b872efb538b0bf4f3/Screen_Shot_2016-06-14_at_11.58.54_AM.png)

After:

![Screen_Shot_2016-06-14_at_11.58.57_AM](/uploads/d9fcfcac0f70dde4e69ff4263e369f65/Screen_Shot_2016-06-14_at_11.58.57_AM.png)

## Does this MR meet the acceptance criteria?

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

cc: @jschatz1

See merge request !4655

Hides award emoji & access level on system notes

## What does this MR do?

Hides award emoji & access level on system notes as they aren't applicable to them notes.

## Screenshots (if relevant)

![Screen_Shot_2016-06-13_at_16.14.03](/uploads/c105c37d0f140dea7480b56242c14ed9/Screen_Shot_2016-06-13_at_16.14.03.png)

See merge request !4629

Refs dropdown is now loaded async

## What does this MR do?

The refs dropdown is loaded async so not to block the page.

## What are the relevant issue numbers?

Part of #18202

## Screenshots (if relevant)

![Screen_Shot_2016-06-07_at_14.41.21](/uploads/8fea12655f96fe7f7008a32677bff037/Screen_Shot_2016-06-07_at_14.41.21.png)

See merge request !4508

Document access request to project & group

## What does this MR do?

Adds documentation that was missing from !3798.

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

I've taken the opportunity to update the images in the "Project users" documentation page, I can remove the commit if it's not welcome!

## What are the relevant issue numbers?

Closes #18584.

## Does this MR meet the acceptance criteria?

- [ ] Tests
  - [ ] 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)

/cc @DouweM 

See merge request !4685

Fallback to group's owners/masters when a project has none for the "access requested email"

## What does this MR do?

From b31c5052:

    Fallback to group's owners/masters when a project has none
    
    A project in a group can have no explicit owners/masters,
    in that case we fallbacks to the group's owners/masters.

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

No.

## Why was this MR needed?

Because of #18757.

## What are the relevant issue numbers?

Fixes #18757.

## Does this MR meet the acceptance criteria?

- [x] No need for CHANGELOG.
- [x] No need for documentation.
- [x] No API support added.
- [x] 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 !4791

POC: Markdown shortcut buttons

## What does this MR do?
Adds markdown shortcut buttons to text area for comments. 

## Are there points in the code the reviewer needs to double check?
Because changing `textarea.val('something')` kills the natural browser undo stack, I had to implement a custom undo stack using state. You can't use the "undoable" state undo pattern because you need to go back to a previous state regardless of cursor position. The undo also adds an undo history item once you delete stuff or press enter.

You can also edit multiple textareas at once and it will keep an undo history for each textarea individually, so the undo state should not collide between textareas.

## Why was this MR needed?
It has been requested multiple times and the competition has it. https://gitlab.com/gitlab-org/gitlab-ce/issues/17185#note_12073433

Libraries are available that already implement this functionality but they are enormous and bloaty. I implemented this in very few lines of code and kept it very simple and as minimal as possible. This was also some competitions approach. I believe so as to not include too much JS. 

Adding extra buttons with new functionality **should only need new HTML and no new JS**.

Only extra complex thing was adding a overridden undo stack, which was made as simple as possible as well.

## What are the relevant issue numbers?
https://gitlab.com/gitlab-org/gitlab-ce/issues/17185#note_12073433

## Screenshots (if relevant)

**NOTE:** One thing you cannot see in this screenshot is that I am pressing <kbd>Cmd</kbd><kbd>Z</kbd> to undo and <kbd>Cmd</kbd><kbd>Shift</kbd><kbd>Z</kbd> to redo which is the undo/redo stack I implemented. <kbd>Ctrl</kbd><kbd>Y</kbd> also works for redo. 
![markdown-editor](/uploads/2517bfb1a7b4269da7fcc4003c88b7f6/markdown-editor.gif)

cc @dzaporozhets for UI

cc @iamphill @alfredo1 for JS review

cc @JobV if you like the idea.

Fixes: #17185

See merge request !4305

Set missing stages on ci builds to 'test' to avoid regressions in the pipelines view

## What does this MR do?

Sets a default stage on old `ci_builds`.

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

Is the migration acceptable for online execution?

## Why was this MR needed?

Old `ci_builds`with no stages cause a regression on the pipelines index view.

## What are the relevant issue numbers?

#17949 

Blocked by https://gitlab.com/gitlab-org/gitlab-ce/merge_requests/4680


See merge request !4381

* upstream/master:
  Add notification_settings:events to schema
  Fixed mobile styling
  Set path for pinned nav cookie
  Fixed placement of close button on merge requests
  using request dot path instead
  Turn note into normal text
  Document environments and deployments
  Tweak grammar
  fix double query string in url
  Broken instructions. git fetch --all --tags doesn't refresh tags

Broken instructions. git fetch --all --tags doesn't refresh tags



See merge request !4092

Add notification_settings:events to schema

See merge request !4800