CE upstream

Closes gitlab-ce#25843, gitlab-ce#25832, and gitlab-ce#25257

See merge request !986

[EE] Allow unauthenticated access to Repositories & Repository Files API GET endpoints

See merge request !985

Sidekiq cluster improvements

Closes #1438

See merge request !987

sidekiq-cluster now supports the same -r/--require option as Sidekiq
itself does. This is needed as Omnibus changes the working directory,
preventing us from properly starting the sidekiq processes.

This redirects STDERR and STDOUT of the various Sidekiq processes to the
sidekiq-cluster process. The logging output of sidekiq-cluster itself
has been changed so it matches Sidekiq's output more closely, making
parsing/grepping easier.

Fixes #1438

Fix Import/Export labels error

Closes #24257

See merge request !8212

Homogenize revert and cherry-pick button styles generated by commits_helper.rb

Closes #25225

See merge request !8053

Geo: Enables nodes to be removed even without proper license

Closes #788

See merge request !978

Account for newlines in commit messages on network graph

Closes #25681 and #21086

See merge request !8131

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

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

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

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

Display error code for U2F errors

See merge request !7305

Apply margin on alert banners only when there is one or more alerts

## What does this MR do?

Fixes extra margin added to all pages by !8151

## Are there points in the code the reviewer needs to double check?

## Why was this MR needed?

## Screenshots (if relevant)

![screenshot](https://gitlab.com/gitlab-org/gitlab-ce/uploads/f8804454e82a61246d10fa026605fbb3/Screen_Shot_2016-12-19_at_2.04.42_PM.png)

## Does this MR meet the acceptance criteria?

- [ ] [Changelog entry](https://docs.gitlab.com/ce/development/changelog.html) added
- [ ] [Documentation created/updated](https://gitlab.com/gitlab-org/gitlab-ce/blob/master/doc/development/doc_styleguide.md)
- [ ] API support added
- Tests
  - [ ] Added for this feature/bug
  - [ ] All builds are passing
- [ ] Conform by the [merge request performance guides](http://docs.gitlab.com/ce/development/merge_request_performance_guidelines.html)
- [ ] Conform by the [style guides](https://gitlab.com/gitlab-org/gitlab-ce/blob/master/CONTRIBUTING.md#style-guides)
- [ ] Branch has no merge conflicts with `master` (if it does - rebase it please)
- [ ] [Squashed related commits together](https://git-scm.com/book/en/Git-Tools-Rewriting-History#Squashing-Commits)

## What are the relevant issue numbers?

Closes #25835

See merge request !8209

Rename SlackNotificationService back to SlackService

## What does this MR do?

See https://gitlab.com/gitlab-org/gitlab-ce/merge_requests/8191#note_20310845

## What are the relevant issue numbers?

Closes https://gitlab.com/gitlab-org/gitlab-ce/issues/25843

/cc @yorickpeterse @stanhu @smcgivern @felipe_artur @ayufan

See merge request !984

Rename SlackNotificationService back to SlackService

## What does this MR do?

See https://gitlab.com/gitlab-org/gitlab-ce/merge_requests/8191#note_20310845

## What are the relevant issue numbers?

Closes https://gitlab.com/gitlab-org/gitlab-ce/issues/25843

/cc @yorickpeterse @stanhu @smcgivern @felipe_artur @ayufan

See merge request !8208