Remove milestones from merge requests when milestones are deleted

Destroying a milestone does not remove it from existing merge requests. This MR fixes that.

Requires f4816372 to pull in as well.

Reported by https://github.com/gitlabhq/gitlabhq/issues/9643

See merge request !1348

Link project repo size to files



See merge request !1374

Remove CI button from project home panel

Since we already have a "Continuous Integration" item in the sidebar now, I don't think we need "CI" on the project page.


See merge request !1372

Use fixed-width icons in CI nav sidebar.



See merge request !1376

Use consistent styling for number of commits in CI nav sidebar

Before:

![Screen_Shot_2015-09-21_at_15.00.28](https://gitlab.com/gitlab-org/gitlab-ce/uploads/9005f606842936d415a3b67890b8af88/Screen_Shot_2015-09-21_at_15.00.28.png)


After:

![Screen_Shot_2015-09-21_at_15.00.43](https://gitlab.com/gitlab-org/gitlab-ce/uploads/08c897b65f82fab5f2c386a0d21c64af/Screen_Shot_2015-09-21_at_15.00.43.png)


See merge request !1375

Reported by https://github.com/gitlabhq/gitlabhq/issues/9643

This reverts commit 3abcab77.

Notification levels can now be set on the Project's main page

![Screen_Shot_2015-09-16_at_7.49.49_PM](https://gitlab.com/gitlab-org/gitlab-ce/uploads/0ac517bdfdc801f0e2115463c3ea9e10/Screen_Shot_2015-09-16_at_7.49.49_PM.png)

The notification settings for a project can now be set directly on the Project's page. The drop down list and the button label reflect the current level.

Saving is done via a remote form submission and if successful shows the user a flash message:

![Screen_Shot_2015-09-16_at_6.09.02_PM](https://gitlab.com/gitlab-org/gitlab-ce/uploads/8a6e1fde5177aa3976cadf59fdb8d375/Screen_Shot_2015-09-16_at_6.09.02_PM.png)

@DouweM can you please review my code. I gave my bestest effort to make in clean and readable.

@rspeicher hopefully we can include it with the 8.0 release, maybe?

/cc @darby 

See merge request !1322

Make Markdown area formatting consistent

Issue #2585 


See merge request !1354

Use GitlabCi::VERSION when checking migration



See merge request !1368

CI migration rake task for GitLab CE

- Uses backup format for final GitLab CI 8.0
- Highly optimized tags migration SQL queries


See merge request !1365

Fail ci builds without yml

Fix for https://gitlab.com/gitlab-org/gitlab-ce/issues/2551

See merge request !1349

Fix Markdown links not showing up in dashboard activity feed

Closes #2586

See merge request !1353

Fix reply by email for comments on a specific line in a diff/commit.

Fixes #2363.

See merge request !1364

Add Gmail actions button for GitLab doc.

Resolves #1517 by adding doc with some notes.

See merge request !1327

Fix 500 when showing project page and there's no CI project present

This fixes 500 when:
1. GitLabCiService is active
2. There's no project in ci_projects table


See merge request !1338

Closes #2586

Apply new design to pagination
Signed-off-by: Dmitriy Zaporozhets <dmitriy.zaporozhets@gmail.com>

cc @skyruler 

See merge request !1362

Style CI project/build list

* return `bs-callout` css class to fix few UI issues
* refactor build status helpers
* style CI project page (#2545)
* style build page by re-using existing UI components
* style CI commit page  by re-using existing UI components
Signed-off-by: Dmitriy Zaporozhets <dmitriy.zaporozhets@gmail.com>

See merge request !1339

Removed format validation

**What does this MR do?**

Removals format validation for drone token

**Are there points in the code the reviewer needs to double check?**

Nothing

**Why was this MR needed?**

because drone migrated to JWT tokens and JWT token doesn't valid with current format ( i don't know how many symbols JWT can use for this )

See merge request !1359

Bump devise-two-factor to 2.0.0

Addresses internal https://dev.gitlab.org/gitlab/gitlabhq/issues/2605

See https://github.com/tinfoil/devise-two-factor/pull/43

See merge request !1363

fixes link to reply_by_email docs