* Update metric names to match current release.
* Improve descriptions.
* Improve examples to show more query language functionality.

Memory:
* Show use of `or` function.
* Automatically select "MemAvailable" kernel metric if possible.

CPU:
* Show use of `avg without ...`.
* Show CPU utilization per node.

Network:
* Show use of `!=` label matching.
* Don't show "localhost" metrics.

Merge branch '51271-error-500-due-to-encoding-issues-when-when-attempting-to-access-issues-api' into 'master'

Resolve "Error 500 due to encoding issues when when attempting to access issues API"

Closes #51271

See merge request gitlab-org/gitlab-ce!21680

- utilize the 'out' method to output the 'fence_info',
  which converts to utf8
- output 'sourcepos' again

Filter any parameters ending with "key" in logs

See merge request gitlab-org/gitlab-ce!21688

Use gitlab-ui loading icon

See merge request gitlab-org/gitlab-ce!21659

Rails does a partial match for strings in the filter_parameters
configuration, so the parameter "key" causes "key_id" to be filtered
even though it's a useful parameter for debugging internal API issues.

We now revise this filter to make any parameter ending with "key" is
filtered.

Relates to https://gitlab.com/gitlab-com/gl-infra/production/issues/463

Resolve "500 Internal Server Error: Cherrypick commit with empty branch name"

Closes #50677

See merge request gitlab-org/gitlab-ce!21501

Generate JUnit report for Karma tests

See merge request gitlab-org/gitlab-ce!21473

Explicitly use bootstrap 4.1.1

Closes #51362

See merge request gitlab-org/gitlab-ce!21683

Remove unused GlModal import in delete wiki modal

See merge request gitlab-org/gitlab-ce!21677

Fix the group and project activity pages

Closes #51375

See merge request gitlab-org/gitlab-ce!21674

Add empty state illustration information in job API

Closes #51112

See merge request gitlab-org/gitlab-ce!21532

[CE] Fix rails 5 deprecation warnings

See merge request gitlab-org/gitlab-ce!21673

Resolve "[SCSS Variables Cleanup] Combine all duplicated hex colors in variables.scss", Part 1

See merge request gitlab-org/gitlab-ce!21375

Enable frozen string in vestigial files

See merge request gitlab-org/gitlab-ce!21665

Use Rails.root for CommonMetricsImporter

Closes #51333

See merge request gitlab-org/gitlab-ce!21664

Add ability to skip user email confirmation with API

Closes #50876

See merge request gitlab-org/gitlab-ce!21630

Fixes rails 5 deprecation warnings in `config/` files

Add sorting for labels on labels page

See merge request gitlab-org/gitlab-ce!21642

Fix workhorse temp path for namespace uploads

Closes gitlab-ee#7009

See merge request gitlab-org/gitlab-ce!21650

Remove jquery.scss; Combine multiple duplicate grays into global gray variables; Remove unused styles in common.scss

Resolve "Filter bar height changes when items are added"

Closes #49943

See merge request gitlab-org/gitlab-ce!21609

Resolve "Project export broken when avatar is set"

Closes #51318

See merge request gitlab-org/gitlab-ce!21649

Partially addresses #47424.

Add steps for closing product discovery issue

See merge request gitlab-org/gitlab-ce!21273

QA: Add support for testing Git over HTTP with LDAP users

See merge request gitlab-org/gitlab-ce!21354

Rails 5: fix issue move service

See merge request gitlab-org/gitlab-ce!21616

In rails 5, the attributes method for an enum returns the name
instead of the database integer.