Add SCSS Lint, CSSComb config file, run SCSS Lint in GitLab CI, add documentation for SCSS Style Guide.

See !3069 for more information.

Improved search results filter dropdown

## Current

Currently filter dropdowns on search results page can be **very** long and off the page

![Screen_Shot_2016-03-11_at_15.25.24](/uploads/3418b0a6f4f8a0a8bd2441b53502c574/Screen_Shot_2016-03-11_at_15.25.24.png)

## New

Changed over to the new dropdown

![Screen_Shot_2016-03-11_at_15.29.06](/uploads/2d3a4a9b3e50f3e0fc1748a026cd5905/Screen_Shot_2016-03-11_at_15.29.06.png)

See merge request !3183

Upgrade `omniauth-saml` to 1.5.0 and document it's new capabilities.

With this MR I'm upgrading `omniauth-saml` to 1.5.0 to include new and improved functionality. See https://github.com/omniauth/omniauth-saml/blob/master/CHANGELOG.md for more details.

This MR includes new documentation, so @axil can you also take a look?

/cc @DouweM 

See merge request !3170

[ci skip]

Updated UI of award emoji

Closes #13878 

See merge request !3028

Removed benchmark suite and its documentation

Related issue: gitlab-org/gitlab-ce#13718

See merge request !3137

Updated gitlab_git to 9.0.1

This includes gitlab-org/gitlab_git!69 and will hopefully solve
gitlab-org/gitlab-ce#13808.

See merge request !3123

Fixes issue with issue sidebar toggle button not working

Closes #14195

See merge request !3165

Account settings

Closes #13854

![](https://gitlab.com/gitlab-org/gitlab-ce/uploads/4802a7b4f74f17d25a611ed1a2200445/account-settings.png)

See merge request !3039

Added discard button to comment form

Also changed the labels on the buttons to better match the action they are completing.

Closes #8057

See merge request !3085

Add error for ajax:error when submitting comments

Fixes #13814
![Screen_Shot_2016-02-25_at_1.54.56_PM](/uploads/d70d706d306079df1b00d70f09affb63/Screen_Shot_2016-02-25_at_1.54.56_PM.png)
cc @dblessing 

See merge request !2976

Support YAML alias/anchor usage in .gitlab-ci.yml

This allows to reuse one job as a template for another one:

```
job1: &JOBTMPL
  script: execute-script-for-job

job2: *JOBTMPL

```

This also helps to solve some of the issues in gitlab-org/gitlab-ci#342

See merge request !2958

Affix the build scroll controls

Closes #4709

See merge request !3109

Added in disable button for 2fa

Moved colours to variables

Closes #13854

Closes #13878

Change all instances of "web hooks" to "webhooks"

See merge request !3169

[ci skip]

OCD hooooooooo!

[ci skip]