Fix error when trying to create a wiki page

Closes #15527, #15569, #15623, #15630, #15637, #15653, #15870, #16558, #16875, #16987, #17016, https://github.com/gitlabhq/gitlabhq/issues/10317.

See merge request !3924

Load the "New Branch" button asynchronously

Here's how it looks like for logged in users:

![new_branch](/uploads/718e3d9016a50a0432b9541dde5ca74c/new_branch.gif)

And here it is for anonymous users (or when a new branch can't be created by a logged in user):

![new_branch_anonymous](/uploads/dce42ee6a7dd7708443cdfdb56389d46/new_branch_anonymous.gif)

See merge request !3855

Updated label links to work correctly for filtering

See !3846#note_5033951

See merge request !3920

Prevent users from deleting Webhooks via API they do not own

Closes https://gitlab.com/gitlab-org/gitlab-ce/issues/15576

See merge request !1959

[ci skip]

Prevent privilege escalation via notes API

Closes https://gitlab.com/gitlab-org/gitlab-ce/issues/15577

See merge request !1964

Fixed width of .search-location-badge as it was causing issues in Safari.

Fixed width of .search-location-badge as it was causing issues in Safari.

Fixes issue #15541 and is a minor CSS only change so [ci skip]

# Before

Safari:
![Screen_Shot_2016-04-24_at_22.35.38](/uploads/74388670fde3af94429d83b954833bd3/Screen_Shot_2016-04-24_at_22.35.38.png)

# After

Safari:
![Screen_Shot_2016-04-24_at_21.59.49](/uploads/177d0d8fda665165dff5006930604fc6/Screen_Shot_2016-04-24_at_21.59.49.png)

Chrome:
![Screen_Shot_2016-04-24_at_21.59.40](/uploads/6764cd5864901210f4f8eff4388fd6db/Screen_Shot_2016-04-24_at_21.59.40.png)

# CSS class referenced in the following files:

`./app/assets/javascripts/search_autocomplete.js.coffee`

`./app/assets/stylesheets/pages/search.scss`

…and is visible on the search bar on every page.

See merge request !3900

Fixes issue with emoji comments not showing correct emoji image

Previously it would look for the unicode character inside the award menu. But this menu might not always be there.

Now, the unicode characters are loaded onto the page in an array which the award emoji that looks in to get the correct emoji unicode character

Fixes #15512

See merge request !3885

Prevent information disclosure via milestone API

Closes https://gitlab.com/gitlab-org/gitlab-ce/issues/15579

See merge request !1961

Prevent XSS via custom issue tracker URL

Fixes https://gitlab.com/gitlab-org/gitlab-ce/issues/15437

See merge request !1955

Prevent information disclosure via new merge request page

Closes https://gitlab.com/gitlab-org/gitlab-ce/issues/15591.

See merge request !1963

Prevent privilege escalation via "impersonate" feature

Closes https://gitlab.com/gitlab-org/gitlab-ce/issues/15548

See merge request !1956

Prevent information disclosure via snippet API

Closes https://gitlab.com/gitlab-org/gitlab-ce/issues/15580

See merge request !1958

Fixes XSS injection

REF: https://gitlab.com/gitlab-org/gitlab-ce/issues/15434

**Without the fix**

![xss1](/uploads/0a7b0b15fb87066965a7c73f1dbaa815/xss1.gif)


**With the fix**

![xss2](/uploads/473cfa0aa80656f24c58aebf1fd97fff/xss2.gif)


See merge request !1952

Fixes window.opener bug

Adds `noreferrer` value to rel attribute for external links

REF: https://gitlab.com/gitlab-org/gitlab-ce/issues/15331

See merge request !1953

Triggers blur after clicking award button

![blur](/uploads/6cd53a5ac314e8048c656685935747e2/blur.gif)

Fixes #15511

See merge request !3881

Fixed issue with project dropdown links not being clickable



See merge request !3870

Fixed issue with assignee object not being returned

Closes #15515

See merge request !3877

Add posibility to define a hidden job without 'script' in .gitlab-ci.yml

References #15451

/cc @ayufan 

See merge request !3849

Fix Error 500 due to stale cache when projects are renamed or transferred

See merge request !3865

Fix license detection to detect all license files, not only known licenses

Fixes #15470.

See merge request !3878

Refactor Todos feature spec to be faster and less brittle

We now only create two Todos instead of 21 when testing pagination, and
we've updated the test to be less brittle when dealing with slower CI
environments.

See merge request !3889

Use the `can?` helper instead of `current_user.can?`

Fixes #15513.

See merge request !3882

Allow middle-click on a Todo row to open in a new tab



See merge request !3899

Add --tags to fetching gitlab-shell to ensure tags are downloaded

Closes #15525

See merge request !3896

Correctly escapes label title in filters

Fixes #15522

See merge request !3880

Move cherry-pick feature specs to proper directory

Cherry pick feature specs were located in `spec/feature/project` directory while we have `spec/feature/projects`.

Later location is consistent with our namespaces (we have `Projects::` namespace, not `Project::`).

See merge request !3875

Bump gitlab-shell to 2.7.2

Closes https://gitlab.com/gitlab-org/gitlab-ce/issues/15525

See merge request !3884

Don't break line in middle of word

<img src="/uploads/cceb1a4212ff7785ace03cd6468edf85/Screen_Shot_2016-04-21_at_3.32.00_PM.png" width="500px">

See merge request !3864

[ci skip]

Allow filtering by Owned projects on dashboard page

Closes #3799 

![Screen_Shot_2016-04-15_at_9.40.52_PM](/uploads/440498c5647bda282304891307931a02/Screen_Shot_2016-04-15_at_9.40.52_PM.png)

See merge request !3762

Add newest enhancements to GH importer docs

[ci skip]

See merge request !3867

Use new Note styleguide



See merge request !3866

Fixes text color on labels in sidebar

Previously the labels in the sidebar would just have `#FFF` text color which could cause problems with a light background color.

With this, the text color comes from the JSON.

See merge request !3846