Fix "A copy of Gitlab::Middleware::Readonly has been removed from the module

See merge request gitlab-org/gitlab-ce!17925

OmniauthInitializer created to allow testing/refactoring of code from devise.rb

See merge request gitlab-org/gitlab-ce!17881

[ci skip]

Fix "A copy of Gitlab::Middleware::Readonly has been removed from the module tree but is still active"

Similar to #34047 and #29327

Add query counts by model to profiler output

See merge request gitlab-org/gitlab-ce!17910

Disables the button when submitting comment.

Closes #39661

See merge request gitlab-org/gitlab-ce!17918

Add docs on CI caching

Closes #32515, #18945, and gitlab-runner#1621

See merge request gitlab-org/gitlab-ce!12183

Move TimeTrackingCollapsedState vue component

See merge request gitlab-org/gitlab-ce!17399

Clarify location of Procfile for mail_room

See merge request gitlab-org/gitlab-ce!17896

- New cache page
- Move manual cache clearing to the new page
- Add all directives of cache in the yaml reference

Update omniauth 1.4.2 -> 1.8

See merge request gitlab-org/gitlab-ce!17763

Backports changes made in https://gitlab.com/gitlab-org/gitlab-ee/merge_requests/5063 to CE

See merge request gitlab-org/gitlab-ce!17909

[Rails5] Add `Gemfile.rails5`

See merge request gitlab-org/gitlab-ce!17761

Issuable list: add tooltips to icons

Closes #43786

See merge request gitlab-org/gitlab-ce!17700

Fixes the web IDE link in tree list opening the wrong URL

Closes #44477

See merge request gitlab-org/gitlab-ce!17900

[Rails5] Update ar5_batching initializer

See merge request gitlab-org/gitlab-ce!17825

[Rails5] Update ar5_pg_10_support initializer

See merge request gitlab-org/gitlab-ce!17826

Remove parser warnings workaround

See merge request gitlab-org/gitlab-ce!17901

Send Gitaly payload for git-upload-archive SSH commands

Closes gitaly#1092

See merge request gitlab-org/gitlab-ce!17903

Add indexes for user activity queries.

Closes #44446

See merge request gitlab-org/gitlab-ce!17890

makes caret go to the right side when closing most right issueboard list

Closes #40913

See merge request gitlab-org/gitlab-ce!17773

Convenient use of concurrent migration helpers

Closes #43887

See merge request gitlab-org/gitlab-ce!17888

NestingDepth (level 5) in framework/dropdowns.scss

See merge request gitlab-org/gitlab-ce!17820

Updated in:
https://gitlab.com/gitlab-org/gitlab-ce/merge_requests/17673

Closes #44446.

Changes empty project avatar to identicon in the IDE

Closes #44298

See merge request gitlab-org/gitlab-ce!17899