Support Wiki pages with dots in slugs

Closes #44780

See merge request gitlab-org/gitlab-ce!24383

Only send one notification for failed remote mirror

Closes #56222

See merge request gitlab-org/gitlab-ce!24381

Fix duplicate project disk path in BackfillLegacyProjectRepositories

Closes #56061

See merge request gitlab-org/gitlab-ce!24213

Add syntax highlighting to suggestion preview

Closes #55945

See merge request gitlab-org/gitlab-ce!24358

Document four backticks feature in markdown

See merge request gitlab-org/gitlab-ce!24349

Add clear_credentials method to ProjectImportData

See merge request gitlab-org/gitlab-ce!24373

Optimization of setup of Main Nav Layout, Contextual Sidebar and Fly Out Nav

Closes #56257

See merge request gitlab-org/gitlab-ce!24362

Refactor only/except configuration policies

See merge request gitlab-org/gitlab-ce!24359

Fix failing MySQL spec due to deadlock condition

Closes #55161

See merge request gitlab-org/gitlab-ce!24378

Ignore Repository::AmbiguousRefError in db/fixtures/development

See merge request gitlab-org/gitlab-ce!24366

Introduce `default:` configuration entry setting that makes it possible
to configure a default value of an entry, what overrides class-level
`def self.default` value.

Backporting a change in ee branch

See merge request gitlab-org/gitlab-ce!23559

Resolve "When merging an MR, the squash checkbox isn't always supported"

Closes #52278

See merge request gitlab-org/gitlab-ce!24296

Remove cancel all jobs button in general jobs list view

Closes #34665

See merge request gitlab-org/gitlab-ce!24010

Retries in Sidekiq and in the remote mirror scheduler can cause repeated
attempts in quick succession if the sync fails. Each failure will then
send an e-mail to all project maintainers, which can spam users
unnecessarily.

Modify the logic to send one notification the first time the mirror
fails by setting `error_notification_sent` to `true` and reset the
flag after a successful sync.

Closes https://gitlab.com/gitlab-org/gitlab-ce/issues/56222

Make parseBoolean idempotent

See merge request gitlab-org/gitlab-ce!24365

`spec/features/uploads/user_uploads_file_to_note_spec.rb` was failing in
master because MySQL detected a deadlock when a DELETE and INSERT for
the same indexed item occurred within a transaction in the `uploads`
table.  Due to InnoDB's next-key locking algorithm
(innodb_locks_unsafe_for_binlog in
https://dev.mysql.com/doc/refman/5.5/en/innodb-parameters.html), InnoDB
sets an exclusive lock for any of the indexed records it encounters, so
the INSERT will fail until the DELETE is committed.

To fix this, we just disable the transaction for MySQL and keep
it for PostgreSQL.

Closes https://gitlab.com/gitlab-org/gitlab-ce/issues/55161

Clarify cluster integration link is for all Kubernetes

See merge request gitlab-org/gitlab-ce!24364

Generate searchable JSDoc documentation

See merge request gitlab-org/gitlab-ce!23583

Externalize strings from `/app/views/projects/project_members`

See merge request gitlab-org/gitlab-ce!23227

Remove all `$theme-gray-{weight}` variables in favor of `$gray-{weight}`

Closes #56266

See merge request gitlab-org/gitlab-ce!24333

This backports changes made in
https://gitlab.com/gitlab-org/gitlab-ee/merge_requests/9134.

Moves shared code into a mixin

See merge request gitlab-org/gitlab-ce!24322

Add Import/Export dev docs

Closes #36055

See merge request gitlab-org/gitlab-ce!23835

Signed-off-by: NRémy Coutable <remy@rymai.me>

GitLab 11.4.3 "Outbound requests" setting path

See merge request gitlab-org/gitlab-ce!22898