Implement fact caching

Fact caching will improve general Ansible performance by default. This
implementation will use the JSONfile configuration because it has no new
dependencies and will provide a similar performance gain as noted through the
use of Redis.

Notes:
* The facts can purged or read by interacting with the default
  JSON file.
* The caching behavior can be turned off by removing the parameter
  fact_caching from the ansible.cfg file.

Change-Id: I007a3bdbaaf30c2ccb4cf42df014ff0d6a943182
Signed-off-by: Gael Chamoulaud <gchamoul@redhat.com>

ansible.cfg

@@ -5,6 +5,10 @@ callback_whitelist = profile_tasks
 host_key_checking = False
 force_color = 1
 pipelining = True
+gathering = smart
+fact_caching = jsonfile
+fact_caching_connection = tmp/
+fact_caching_timeout = 7200
 
 # Attempt to load custom modules whether it's installed system-wide or from a virtual environment
 callback_plugins = /usr/lib/python2.7/site-packages/ara/plugins/callbacks:$VIRTUAL_ENV/lib/python2.7/site-packages/ara/plugins/callbacks:/usr/local/lib/python2.7/dist-packages/ara/plugins/callbacks