New collection: Jetty

[iche033]

• Create gazebodistro file for new collection (example)
  • Add jetty collection gazebodistro#181
• Create gz-<collection> and gz-<collection>-release repositories (example source, example release)
  • https://github.com/gazebosim/gz-jetty
  • https://github.com/gazebo-release/gz-jetty-release
• Create homebrew-simulation formula for new collection (example)
  gz-jetty: alias to gz-ionic osrf/homebrew-simulation#2832
• Create collection view on release-tools and build nightlies (example)
  Add jetty collection to gz-collections.yaml #1199
• Add collection to buildfarmer dashboard (example) / scripts (example)
  • buildfarmer repo / dashboard no longer used
• Add docs for new collection (example)
  • Add jetty doc and tutorials gazebosim/docs#524
• Add new collection label:
  • Add to pr-collection-labeler (example)
    • Add Jetty pr-collection-labeler#36
  • Add to all libraries (handy script)