Bump src/cloud_controller_ng:

Alex Suraci (2):
      use :git instead of :github for cf-message-bus
      update Gemfile.lock

Alex Suraci and Gregg Van Hove (1):
      pass message bus through to component registration

Alex Suraci, Austin Vance, Gregg Van Hove and Maria Shaldibina (1):
      extract message bus interaction into its own gem