The big plan in motion, see https://gitlab.com/gitlab-org/gitlab-ce/issues/3349

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