New CI YAML features

This introduces a couple of small `.gitlab-ci.yml` features:

1. Documentation for: Allow to use YAML anchors when parsing the `.gitlab-ci.yml`: https://gitlab.com/gitlab-org/gitlab-ce/merge_requests/2958
2. Ignore jobs that start with `.`
3. Allow to pass name of created artifacts archive in `.gitlab-ci.yml`
4. Allow to define on which builds the current one depends on

These are really small changes so it makes not sense to create a separate merge requests for them.

@axil Could you review the documentation part?

The implementation on GitLab Runner side: https://gitlab.com/gitlab-org/gitlab-ci-multi-runner/merge_requests/113.

Fixes: https://gitlab.com/gitlab-org/gitlab-ce/issues/13755 https://gitlab.com/gitlab-org/gitlab-ce/issues/14211 https://gitlab.com/gitlab-org/gitlab-ce/issues/3423

cc @grzesiek @axil @DouweM 


See merge request !3182

Improve award emoji test reliability and eliminate sleeps

Closes #14129

See merge request !3195

Left sidebar overlaps the content on mobile devices

On mobile, the navigation sidebar will always revert to being hidden. When clicking the toggle, it will then go over the top of the content - rather than push the content.

See merge request !3087

Add unit specs for `Note#active?`

See merge request !3133

Changed project home icon

Closes #14196

![Screen_Shot_2016-03-14_at_16.01.48](/uploads/0039c0c3afe0bf560368d2b910e2a93f/Screen_Shot_2016-03-14_at_16.01.48.png)

See merge request !3207

Bring from EE: Share Project with Group

- [x] Models and migrations
- [x] Logic, UI
- [x] Tests
- [x] Documentation
- [x] Share with group lock
- [x] Api feature
- [x] Api docs
- [x] Api tests
Signed-off-by: Dmitriy Zaporozhets <dmitriy.zaporozhets@gmail.com>

For #12831 

cc @DouweM @rspeicher @vsizov

See merge request !3186

Closes #14196

Prepare docs for 8.6 RC1

[ci skip]

See merge request !3173

Don't remove `ProjectSnippet#expires_at` from API

See https://gitlab.com/gitlab-org/gitlab-ce/merge_requests/3103

This partially reverts commit 836d5930.

See merge request !3144

[ci skip]

Fixed tests for MR & issue filters

See merge request !3203

Remove sleeps from network graph feature spec

Also removed a double negative in the step description

See merge request !3199

Changed breakpoint class into singleton

This class checks the current bootstrap breakpoint

Use Capybara find methods and remove sleeps in feature specs in "All Issues" filter

Fixes sporadic build failures (e.g. https://gitlab.com/gitlab-org/gitlab-ce/builds/856233)

See merge request !3198

[ci skip]

Closes #14129

Implements upcoming filter in milstones

![Imgur](http://i.imgur.com/Oc2LZrF.png)

@DouweM @JobV I think this is what you wanted :) Lemme know if it there is something that need changing
Had alot of fun doing it!

Closes https://gitlab.com/gitlab-org/gitlab-ce/issues/14102

See merge request !3148

Redirect host check

Fixes https://dev.gitlab.org/gitlab/gitlabhq/issues/2649

Fixes https://gitlab.com/gitlab-org/gitlab-ce/issues/13956

See merge request !1945

Fixes
https://dev.gitlab.org/gitlab/gitlabhq/issues/2649
https://gitlab.com/gitlab-org/gitlab-ce/issues/13956

Signed-off-by: Dmitriy Zaporozhets <dmitriy.zaporozhets@gmail.com>

[ci skip]

Reduce example documentation.

We should not duplicate indexes between the top level and lower level.

See merge request !3162