ha/glance-fs: avoid a race condition

ha/glance-fs: avoid a race condition

Create the glance-fs Pacemaker resource on one node (pacemaker master)
instead of all nodes, and set verify_on_create to True.

* It will avoid a race condition if Puppet is applied on 2 nodes on the
  same time, so the filesystem is attempted to be created once.
* Verify with psc that the resource has been correctly created.

The full context of the bug is decribed here:
https://bugzilla.redhat.com/show_bug.cgi?id=1319384

Change-Id: I625f0879ae56e814664d1433ae47e27148779f12