Fix vulnerability that leaks private labels and milestones

## Summary

This fixes vulnerability that leaks information about private labels and milestones because of  insecure direct object reference in issueable create service.
This affects merge requests and issues.

See https://gitlab.com/gitlab-org/gitlab-ce/issues/15439

## Fix

This MR introduces additional check that rejects labels and milestone that does not belong to the same project issue/merg request does.

## Further work

`IssuableBaseService` may benefit from encapsulating filters in separate class/module, which then may improve coherency in this class.

Closes https://gitlab.com/gitlab-org/gitlab-ce/issues/15439

See merge request !1954

This also verify if milestone belongs to correct project before creating
a new issue.

Closes https://gitlab.com/gitlab-org/gitlab-ce/issues/15439

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

Remove the `.distinct` when finding issues

See merge request !3858

Disable 'repository check' feature in 8.7.0

See merge request !3856

Removed JS update templates

See merge request !3814

Remove float from blame link icon

Closes #15413   
<img src="/uploads/af6aea9102e1b42e5e92783ce818863c/Screen_Shot_2016-04-21_at_1.57.56_PM.png" width="200px">



See merge request !3861

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

Refactor the update documentation



See merge request !3822

Add db:migrate:reset task to CI
Signed-off-by: Dmitriy Zaporozhets <dmitriy.zaporozhets@gmail.com>

cc @DouweM @stanhu 

See merge request !3788

Instrument Gitlab::GitAccess/GitAccessWiki



See merge request !3859

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

Fixes "create label" functionality on label dropdown

**Issue sidebar**

![label_dropdown](/uploads/2a056136fc88626530fc275ded0c2aa3/label_dropdown.gif)

**Issues page**

![label_dropdown_issues](/uploads/965fd20f5b206499e9b11a64556c5240/label_dropdown_issues.gif)



See merge request !3670

Fix undefined local variable error in Invalid MR template

Closes #15408

See merge request !3857

This is not needed anymore after !3815.
Signed-off-by: Rémy Coutable <remy@rymai.me>

Diff highlight fixes

This fixes a couple of issues with linking/highlight diff lines:

- Fixed issue with lines not being selectable when expanding diff
- Fixed issue with incorrect line being highlighted if line is in discussion view

See merge request !3725

Closes #15408

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

File name change appears on one line

Closes #15445

<img src="/uploads/51714555be63af16b810cf528de49192/Screen_Shot_2016-04-21_at_9.22.43_AM.png" width="500px">

See merge request !3854

Fixed issue with author link color on dark diffs

Correctly added a color to the author link

![Screen_Shot_2016-04-21_at_08.55.05](/uploads/ffa9e12e868c7b71fa4dd9244114274a/Screen_Shot_2016-04-21_at_08.55.05.png)

Fixes #15444

See merge request !3847

Use SIGTERM during Sidekiq memory shutdown

This makes the memory killer behave more like 'sidekiqctl stop'.

Closes https://gitlab.com/gitlab-org/gitlab-ce/issues/15359

Closes https://gitlab.com/gitlab-org/gitlab-ce/issues/14462

See merge request !3853

It still causes too many false alarms.

Filter labels by including ALL filter titles

Fixed query to use `AND` and not `OR`. Refactored relevant specs

See merge request !3815

This makes the memory killer behave more like 'sidekiqctl stop'.

Revert "Merge branch 'sentry-js' into 'master'"

This reverts commit 0f309794, reversing
changes made to 1e596fef.

See merge request !3851

Implement top navigation for profile area

Main idea is to keep left sidebar static so user is not confused by
changing context. Instead we put changing navigation with changing
content in one main block. I used profile area as a simplest way to 
implement and test this concept. Your feedback is welcome in comments

For https://gitlab.com/gitlab-org/gitlab-ce/issues/14354#note_4878536Signed-off-by: Dmitriy Zaporozhets <dmitriy.zaporozhets@gmail.com>

See merge request !3824