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_image_load.py

@@ -21,6 +21,17 @@ description:
   - Load one or multiple Docker images from a C(.tar) archive, and return information on
     the loaded image(s).
 
+extends_documentation_fragment:
+  - community.docker.docker.api_documentation
+  - community.docker.attributes
+  - community.docker.attributes.actiongroup_docker
+
+attributes:
+  check_mode:
+    support: none
+  diff_mode:
+    support: none
+
 options:
   path:
     description:
@@ -28,9 +39,6 @@ options:
     type: path
     required: true
 
-extends_documentation_fragment:
-  - community.docker.docker.api_documentation
-
 notes:
   - Does not support C(check_mode).