Expand Git instrumentation

This instruments some extra `Gitlab::Git` code as well as a collection of `Rugged` constants.

See merge request !2664

Increase LFS objects size column

Fixes #12745

Increases the `size` column integer limit to an 8-byte integer. This allows for a max value of `9223372036854775807` which is 9,223,372,036 GB. That should do it 😃

I tested this by first reproducing the error (push a file larger than 2.1 GB). The error was:

```
RangeError (3145728000 is out of range for ActiveRecord::ConnectionAdapters::PostgreSQL::OID::Integer with limit 4):
  lib/gitlab/lfs/response.rb:232:in `store_file'
  lib/gitlab/lfs/response.rb:170:in `render_lfs_upload_ok'
  lib/gitlab/lfs/response.rb:51:in `block in render_storage_upload_store_response'
  lib/gitlab/lfs/response.rb:204:in `render_response_to_push'
  lib/gitlab/lfs/response.rb:50:in `render_storage_upload_store_response'
  lib/gitlab/lfs/router.rb:76:in `put_response'
  lib/gitlab/lfs/router.rb:20:in `try_call'
  lib/gitlab/backend/grack_auth.rb:41:in `call'
  lib/gitlab/backend/grack_auth.rb:18:in `call_with_kerberos_support'
  lib/gitlab/backend/grack_auth.rb:8:in `call'
```

Then I ran this migration and pushed the file again. It uploaded successfully.

See merge request !2644

Backport LDAP user assignment changes from EE

See https://gitlab.com/gitlab-org/gitlab-ee/merge_requests/146

See merge request !2641

Update sentry-raven gem.

Should resolve `fatal: Not a git repository (or any of the parent directories): .git` warnings.

Fixes #12657

See merge request !2636

Correctly determine MR diff base when MR has merge conflicts

Fixes https://gitlab.com/gitlab-org/gitlab-ce/issues/12779

See merge request !2632

Fix highlighting in blame view.

See merge request !2630

[ci skip]

[ci skip]

Fix CI runner version not being properly updated when asked for a build

Due to broken implementation of attribute_for_keys the runner information was not updated correctly.

This MR adds test to check that such scenario will never happen again.

See merge request !2618

Use generic method to checks if artifacts are available

Closes #12626

See merge request !2576

Increase contrast between highlighted code comments and inline diff marker.

Fixes https://gitlab.com/gitlab-org/gitlab-ce/issues/12737.

It was especially bad in Monokai, better now.

See merge request !2629

[ci skip]

Bug/jschatz1/file browser lines

Fixes #12725 

![Screen_Shot_2016-01-26_at_11.19.39_AM](/uploads/c5f5a143926600e02de4cfc0687ed8dd/Screen_Shot_2016-01-26_at_11.19.39_AM.png)


See merge request !2615

Instrument Gitlab::Git::Repository



See merge request !2528

Update gitlab_git & use new method for counting branches

Corresponding gitlab_git merge request detailing some of the rationale behind this: https://gitlab.com/gitlab-org/gitlab_git/merge_requests/62

Fixes #12418

See merge request !2535

Bump Workhorse version to 0.6.2

Fix for #12634 has been introduced in gitlab-org/gitlab-workhorse!34.

See merge request !2616

[ci skip]

Fix import redirect loop

Fixes #11864 

See merge request !2606

Correct arity for instrumented methods w/o args

This should fix the problem of imports not working. See https://gitlab.com/gitlab-org/gitlab-ce/issues/12450#note_3380730 for the details/context of these changes.

See merge request !2602

Highlight note code and edit preview

More highlighting fixes! Highlighting wasn't applied all the way for
code in notes, diff notes diffs and diff preview (on the file edit page).

The CSS changes further unify the styling for file-content highlighting,
diff highlighting and note code highlighting.

See merge request !2594

Update rails, rails-html-sanitizer, and nokogiri for security fixes

See https://dev.gitlab.org/gitlab/gitlabhq/issues/2643

See merge request !2603

Rails updated to 4.2.5

I hope it'll fix weird spec failing (according to https://github.com/rails/rails/pull/22383)

@dzaporozhets @yorickpeterse 

See merge request !2591

Make deleted line background color for Solarized Dark a little darker

The difference is very slight, and I don't even _use_ Solarized Dark, but this annoyed me.

See merge request !2563

Diff highlight themes

Fixes https://gitlab.com/gitlab-org/gitlab-ce/issues/12484

See merge request !2530

Allow empty Mysql password on CI

[ci skip]

See merge request !2558

Fix Error 500 when doing a search for merge requests

Potential fix for #11547

See merge request !2525

Remove unreleased note from changelog (8-4-stable)



See merge request !2556

[ci skip]

Fix grammar and typos in file finder docs



See merge request !2547

Fix MR diff 'Edit' button

It now works and has the right size.

See merge request !2542

More highlighted diff fixes

See merge request !2545

Make sure non-highlighted diffs are still escaped

Fixes https://gitlab.com/gitlab-org/gitlab-ce/issues/12521

See merge request !2544

File finder can be invoked from anywhere!



See merge request !2543

Add method to calculate total size of artifacts in subpath

See merge request !2500

Add file finder documentation

Closes #7966 

See merge request !2541

Do not use progress bar when downloading build artifacts

Closes #12491

See merge request !2531