Add latest changes made on ansible repo that were not backported here

Author: rrey

callback_plugins/grafana_annotations.py

@@ -21,7 +21,7 @@
     author: "Rémi REY (@rrey)"
     description:
       - This callback will report start, failed and stats events to Grafana as annotations (https://grafana.com)
-    version_added: "2.5"
+    version_added: "2.6"
     requirements:
       - whitelisting in configuration
     options:
@@ -34,13 +34,14 @@
           - section: callback_grafana_annotations
             key: grafana_url
       validate_grafana_certs:
-        description: (bool) validate the SSL certificate of the Grafana server. (For HTTPS url)
+        description: validate the SSL certificate of the Grafana server. (For HTTPS url)
         env:
           - name: GRAFANA_VALIDATE_CERT
         ini:
           - section: callback_grafana_annotations
             key: validate_grafana_certs
         default: True
+        type: bool
       http_agent:
         description: The HTTP 'User-agent' value to set in HTTP requets.
         env:
@@ -135,7 +136,7 @@ class CallbackModule(CallbackBase):
     and put the plugin in <path_to_callback_plugins_folder>
     """
 
-    CALLBACK_VERSION = 1.0
+    CALLBACK_VERSION = 2.0
     CALLBACK_TYPE = 'aggregate'
     CALLBACK_NAME = 'grafana_annotations'
     CALLBACK_NEEDS_WHITELIST = True