minor_changes:
- "docker_container, docker_network, docker_volume - return facts as regular variable additionally to
   facts. This is now the preferred way to obtain results."
- "docker_service - return facts as regular variable ``service_facts``; this is a dictionary mapping
   service names to container dictionaries. The facts are still returned, but it is recommended to
   use ``register`` and ``service_facts`` in the future."