Document attributes (#497)

* Add 'docker' action group attribute.

* Compatibility with older ansible-core releases.

* Fix typo.

* Docment standard attributes.

* Improve docs.

* Add shortcuts for common combinations.

plugins/modules/docker_swarm_service.py

@@ -19,6 +19,19 @@ short_description: docker swarm service
 description:
   - Manages docker services via a swarm manager node.
   - This modules does not support updating services in a stack.
+
+extends_documentation_fragment:
+  - community.docker.docker
+  - community.docker.docker.docker_py_2_documentation
+  - community.docker.attributes
+  - community.docker.attributes.actiongroup_docker
+
+attributes:
+  check_mode:
+    support: full
+  diff_mode:
+    support: full
+
 options:
   args:
     description:
@@ -629,9 +642,6 @@ options:
     type: list
     elements: str
     version_added: 2.2.0
-extends_documentation_fragment:
-- community.docker.docker
-- community.docker.docker.docker_py_2_documentation
 
 requirements:
   - "L(Docker SDK for Python,https://docker-py.readthedocs.io/en/stable/) >= 2.0.2"