Merge branch 'list-multiple-clusters' of https://gitlab.com/gitlab-org/gitlab-ce into list-multiple-clusters

* 'list-multiple-clusters' of https://gitlab.com/gitlab-org/gitlab-ce:
  Fix symbolization error in #clusters
  Add specs for scoping in ClustersController
  Add pagination specs for ClustersController
  Add specs for cluster counters
  Use current_user in ClustersController#clusters
  Add specs for ClustersFinder

Finishes tabs & table
Updates e2e tests

* master: (22 commits)
  static-analysis fix
  refactored the hashed repository name
  removed 'only once' from the docs
  static analysis fix
  added changelog
  ignore hashed repositories when doing rake gitlab:cleanup:dirs
  Update prometheus Gem to fix compilation on centos 6 duo to GCC not recognizing `std=c11` option
  Add a feedback mechanism to `package-qa` manual action
  Update svg external dependency
  Drastically improve project search performance by no longer searching namespace name
  Deduplicate protected ref human_access_levels
  Fix ProtectedBranch access level validations
  Address feedback for AWS Runner autoscale article
  Clarify usage of Runner limit and AWS tags
  Finish rest of the sections
  Finish all sections except docker.machine
  Add runners.cache section
  Add Runner registration info
  Clear up sections
  Add skeleton
  ...

Merge branch 'list-multiple-clusters' of https://gitlab.com/gitlab-org/gitlab-ce into list-multiple-clusters

* 'list-multiple-clusters' of https://gitlab.com/gitlab-org/gitlab-ce:
  Simplify Clusters::CreateService cluster check

Upgrade jQuery to 2.2.4

Closes #40481

See merge request gitlab-org/gitlab-ce!15570

removed 'only once' from the docs

Closes #39261

See merge request gitlab-org/gitlab-ce!15601

ignore hashed repositories when doing rake gitlab:cleanup:dirs

Closes #40352

See merge request gitlab-org/gitlab-ce!15600

Update svg external dependency

See merge request gitlab-org/gitlab-ce!15596

Add tests
Update empty state
[ci skip]

Add article on autoscaling GitLab Runner on AWS

Closes #39650

See merge request gitlab-org/gitlab-ce!15313

Update prometheus Gem to fix compilation on centos 6 due to GCC not recognizing `std=c11` option

Closes omnibus-gitlab#2988

See merge request gitlab-org/gitlab-ce!15598

Fix ProtectedBranch access level validations

See merge request gitlab-org/gitlab-ce!15586

Drastically improve project search performance by no longer searching namespace name

Closes #40510 and #39623

See merge request gitlab-org/gitlab-ce!15590

Add a feedback mechanism to `package-qa` manual action

Closes #40431

See merge request gitlab-org/gitlab-ce!15538

* master: (53 commits)
  Updated timeago.js
  Prevent 500 error when inspecting job after trigger was removed
  Add classList polyfill for IE classList.toggle(.., force)
  Use feature flag instead of application settigns to control if method calls should be instrumented
  Rename wip to worker_id
  add missing schema entry and application settigns helper
  Use only real duration to measure method call performance via Prometheus
  check method timing threshold when observing method performance
  Add changelog for #15558
  Reenable prometheus metrics
  Move prometheus middle ware to prometheus initialized.
  Fix WIP system note not being created
  Update CHANGELOG.md for 10.2.2
  Fix hashed storage for attachments bugs
  Rename fetch_refs to refmap
  Clean up repository fetch and mirror methods
  Fix pulling and pushing using a personal access token with the sudo scope
  Allow password authentication to be disabled entirely
  Simplify the DB changes checklist
  Added Rubocop config for background migrations
  ...