Add glance cache cleaner job

On nodes where we set up glance, we currently don't set up a
glance cache cleaning job.  This is a recommended practice as
it can allow glance images to take up excess disk space due to
images that are in invalid/stuck state remaining in the cache
(refer to http://docs.openstack.org/developer/glance/cache.html).
This patch adds glance::cache::cleaner to the glance_all
class group so that a cleaner job gets added to nodes running
glance.

Change-Id: Ifb6b66857ff891840517e18c9794963f80b0409e
Implements: blueprint add-glance-cache-cleaner