Clean up module documentation (#36909)

* Clean up module documentation

This PR includes:
- Removal of `default: None` (and variations)
- Removal of `required: false`
- Fixing booleans and `type: bool` where required

* Fix remaining (new) validation issues

lib/ansible/modules/database/misc/elasticsearch_plugin.py

@@ -33,49 +33,36 @@ options:
     state:
         description:
             - Desired state of a plugin.
-        required: False
         choices: ["present", "absent"]
         default: present
     url:
         description:
             - Set exact URL to download the plugin from (Only works for ES 1.x)
-        required: False
-        default: None
     timeout:
         description:
             - "Timeout setting: 30s, 1m, 1h..."
             - Only valid for Elasticsearch < 5.0. This option is ignored for Elasticsearch > 5.0.
-        required: False
         default: 1m
     plugin_bin:
         description:
             - Location of the plugin binary. If this file is not found, the default plugin binaries will be used.
             - The default changed in Ansible 2.4 to None.
-        required: False
-        default: None
     plugin_dir:
         description:
             - Your configured plugin directory specified in Elasticsearch
-        required: False
         default: /usr/share/elasticsearch/plugins/
     proxy_host:
         description:
             - Proxy host to use during plugin installation
-        required: False
-        default: None
         version_added: "2.1"
     proxy_port:
         description:
             - Proxy port to use during plugin installation
-        required: False
-        default: None
         version_added: "2.1"
     version:
         description:
             - Version of the plugin to be installed.
               If plugin exists with previous version, it will NOT be updated
-        required: False
-        default: None
 '''
 
 EXAMPLES = '''

lib/ansible/modules/database/misc/kibana_plugin.py

@@ -31,42 +31,33 @@ options:
     state:
         description:
             - Desired state of a plugin.
-        required: False
         choices: ["present", "absent"]
         default: present
     url:
         description:
             - Set exact URL to download the plugin from.
               For local file, prefix its absolute path with file://
-        required: False
-        default: None
     timeout:
         description:
             - "Timeout setting: 30s, 1m, 1h..."
-        required: False
         default: 1m
     plugin_bin:
         description:
             - Location of the plugin binary
-        required: False
         default: /opt/kibana/bin/kibana
     plugin_dir:
         description:
             - Your configured plugin directory specified in Kibana
-        required: False
         default: /opt/kibana/installedPlugins/
     version:
         description:
             - Version of the plugin to be installed.
               If plugin exists with previous version, it will NOT be updated if C(force) is not set to yes
-        required: False
-        default: None
     force:
         description:
             - Delete and re-install the plugin. Can be useful for plugins update
-        required: False
-        choices: ["yes", "no"]
-        default: no
+        type: bool
+        default: 'no'
 '''
 
 EXAMPLES = '''

lib/ansible/modules/database/misc/redis.py

@@ -41,7 +41,6 @@ options:
     master_host:
         description:
             - The host of the master instance [slave command]
-        default: null
     master_port:
         description:
             - The port of the master instance [slave command]

lib/ansible/modules/database/misc/riak.py

@@ -28,47 +28,35 @@ options:
   command:
     description:
       - The command you would like to perform against the cluster.
-    required: false
-    default: null
     choices: ['ping', 'kv_test', 'join', 'plan', 'commit']
   config_dir:
     description:
       - The path to the riak configuration directory
-    required: false
     default: /etc/riak
   http_conn:
     description:
       - The ip address and port that is listening for Riak HTTP queries
-    required: false
     default: 127.0.0.1:8098
   target_node:
     description:
       - The target node for certain operations (join, ping)
-    required: false
     default: riak@127.0.0.1
   wait_for_handoffs:
     description:
       - Number of seconds to wait for handoffs to complete.
-    required: false
-    default: null
   wait_for_ring:
     description:
       - Number of seconds to wait for all nodes to agree on the ring.
-    required: false
-    default: null
   wait_for_service:
     description:
       - Waits for a riak service to come online before continuing.
-    required: false
-    default: None
     choices: ['kv']
   validate_certs:
     description:
       - If C(no), SSL certificates will not be validated. This should only be used
         on personally controlled sites using self-signed certificates.
-    required: false
+    type: bool
     default: 'yes'
-    choices: ['yes', 'no']
     version_added: 1.5.1
 '''