Prettify all the things (part 7)

See merge request gitlab-org/gitlab-ce!22257

Fix usage ping link

Closes #53070

See merge request gitlab-org/gitlab-ce!22545

Fix secpick to use EE and guess branch name

Closes gitlab-org/release/tasks#483

See merge request gitlab-org/gitlab-ce!22517

Backport scss changes for https://gitlab.com/gitlab-org/gitlab-ee/merge_requests/7973

See merge request gitlab-org/gitlab-ce!22503

clarify auto review apps deployment, jobs skipped by license, disabling at…

See merge request gitlab-org/gitlab-ce!22403

Also count specs in new files in Danger check

See merge request gitlab-org/gitlab-ce!22543

Remove unused rails5-variables

See merge request gitlab-org/gitlab-ce!22561

Limit flash notice width for fixed layout and improve spacing for fluid layout

Closes #32868

See merge request gitlab-org/gitlab-ce!16482

Add transparent background to markdown header tabs

Closes #53105

See merge request gitlab-org/gitlab-ce!22565

Request to be a German proofreader

See merge request gitlab-org/gitlab-ce!22337

Add list mode to file browser in diffs

Closes #51859

See merge request gitlab-org/gitlab-ce!22191

Hotfix for Rspec and second storage

See merge request gitlab-org/gitlab-ce!22558

Bump google-protobuf to 3.6.1

See merge request gitlab-org/gitlab-ce!22559

Rails requires a second storage for testing cross shard features. Gitaly
will not boot if this second storage doesn't exist. So this will create
this storage without adding it to the list of storages that Rails knows
about.

They're no longer used and have no effect

It looks like gRPC may have worked around
https://github.com/google/protobuf/issues/4210 via
https://github.com/grpc/grpc/pull/14634.

This is needed to support Ruby 2.5
(https://gitlab.com/gitlab-org/gitlab-ce/merge_requests/22555).

Sync group sidebar template with EE

See merge request gitlab-org/gitlab-ce!22549

Resolve "Endless scroll loader is visible on user profile overview page"

Closes #53023

See merge request gitlab-org/gitlab-ce!22529

Fix link in doc/user/project/repository/branches/index.md

See merge request gitlab-org/gitlab-ce!22554

doc: Fix broken link hrefs for ee and gitlab-versions

See merge request gitlab-org/gitlab-ce!22540

Add instructions on how to enable a feature flag

Closes gitlab-org/release/framework#23

See merge request gitlab-org/gitlab-ce!22518

Correcting a typo

See merge request gitlab-org/gitlab-ce!22511

Administrator documentation for Pages access control

See merge request gitlab-org/gitlab-ce!22146

- Allow to extend nav links for the Group sidebar

Removes duplicate escape from job item

Closes #53013

See merge request gitlab-org/gitlab-ce!22536

Fix ee-compat-check by not modifying frozen strings

Closes #53030

See merge request gitlab-org/gitlab-ce!22527

Add review app

Closes #52188 and #49569

See merge request gitlab-org/gitlab-ce!22010

Update dev security workflow template

See merge request gitlab-org/gitlab-ce!22532