* upstream/master: (337 commits)
Update CHANGELOG for !4659
Center the header logo for all Devise emails
Add previews for all customized Devise emails
Customize the Devise `unlock_instructions` email
Customize the Devise `reset_password_instructions` email
Customize the Devise `password_change` emails
Use gitlab-git 10.2.0
Use Git cached counters on project show page
Fix indentation scss-lint errors
Added title attribute to enties in tree view Closes#18353
Banzai::Filter::ExternalLinkFilter use XPath
Reduce queries in IssueReferenceFilter
Use gitlab_git 10.1.4
Fixed ordering in Project.find_with_namespace
Fix images in emails
Banzai::Filter::UploadLinkFilter use XPath
Turn Group#owners into a has_many association
Make project_id nullable
CHANGELOG [ci skip]
CHANGELOG [ci skip]
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Add notice about GitLab Runner to requirements docs
This is related to #14589, and problems that may stem from running
GitLab Runner on same machine user installed GitLab web app on.
See merge request !3518
