Extract code from Issues::MoveService

See merge request gitlab-org/gitlab-ee!8402

Make sure there's only one slash as path separator

See merge request gitlab-org/gitlab-ee!8084

CE upstream - 2018-11-12 18:21 UTC

Closes gitlab-ce#53853

See merge request gitlab-org/gitlab-ee!8408

Fix MergeRequestService erroring out on deleted branch

Closes #53853

See merge request gitlab-org/gitlab-ce!22989

CE upstream - 2018-11-12 16:21 UTC

Closes gitlab-ce#53781

See merge request gitlab-org/gitlab-ee!8407

Disable CODEOWNERS for the time being

See merge request gitlab-org/gitlab-ce!22991

When a branch is deleted, the push commit IDs is an empty array.
The previous change would attempt to call `[].exists?`, which is
invalid. Fix this by returning `MergeRequestDiffCommit.none` instead.

Closes https://gitlab.com/gitlab-org/gitlab-ce/issues/53853

Removes feature flag for ciEnvironmentsStatusChanges

Closes #52937

See merge request gitlab-org/gitlab-ce!22947

We can move the file back to its original location once https://gitlab.com/gitlab-org/gitlab-ee/issues/8396 is fixed.

# Conflicts:
#	.gitlab-ci.yml
#	doc/user/markdown.md

[ci skip]

CE upstream - 2018-11-12 10:21 UTC

Closes #8390

See merge request gitlab-org/gitlab-ee!8400

Bump redis-store to 1.6.0

See merge request gitlab-org/gitlab-ce!22963

Bump mime-types to 3.2.2

See merge request gitlab-org/gitlab-ce!22957

[EE] Comment on any expanded diff line on MRs (with feature-flag)

See merge request gitlab-org/gitlab-ee!8362

Comment on any expanded diff line on MRs (with feature-flag)

Closes #13950

See merge request gitlab-org/gitlab-ce!22914

Set an empty entrypoint for license_management job

Closes #53786

See merge request gitlab-org/gitlab-ce!22955

Remove unnecessary job dependencies

See merge request gitlab-org/gitlab-ce!22961

Remove unnecessary job dependencies

See merge request gitlab-org/gitlab-ee!8391

Changed diff tree filtering to path

Closes #53781

See merge request gitlab-org/gitlab-ce!22978

Resolve "View issue button doesn't work in dashboard modal"

Closes #8370

See merge request gitlab-org/gitlab-ee!8385

Improve initial rendering of discussion notes

See merge request gitlab-org/gitlab-ce!22607

Previously it was using name which could make it hard
to filter for the file you want in a certain folder.

Closes https://gitlab.com/gitlab-org/gitlab-ce/issues/53781

Upgrade whitequark/parser to 2.5.3.0

See merge request gitlab-org/gitlab-ce!22984

Docs: updates docs development guidelines

Closes #53160 and #53115

See merge request gitlab-org/gitlab-ce!22813

Docs: update docs development guidelines

See merge request gitlab-org/gitlab-ee!8363

Extract code to make it easier reusable
- introduce AttributesRewriter and ContentRewriter
  - support group entites when rewriting content
- make Uploader copy_to working for Namespaces

Dangerbot: mention tech writers based on DevOps stage

See merge request gitlab-org/gitlab-ce!22945

Bump Sidekiq and other related gems

See merge request gitlab-org/gitlab-ce!22956

Rails 5 counterpart to the version update from
7fb30b4c