* upstream/master: (889 commits)
  SlackService - respect `notify_only_default_branch` for push events
  Clarify usage ping wording in admin area
  Update incoming emails documents
  Allow to include also descendant group labels
  Update docs on grouping CI jobs
  Support additional LabelsFinder parameters for group labels
  Extend Cluster Applications to install GitLab Runner to Kubernetes cluster
  Remove registry list webpack entry point
  Remove trailing newline that was causing an EE conflict
  Small fixes in Vuex docs
  Remove u2f webpack bundle
  Update documentation WRT to request parameters
  remove common_vue CommonsChunk config
  Fetch commit signatures from Gitaly in batches
  migrate stl_viewer to dynamic import
  migrate sketch_viewer to dynamic import
  migrate pdf_viewer to dynamic import
  migrate notebook_viewer to dynamic import
  migrate balsamiq_viewer to dynamic import
  Add some strings that were missing in gitlab.pot
  ...