Remove policies which had attached to cluster while attaching policy
Remove policies which had attached to cluster while attaching policy

Available policies shouldn't contain the policies which had attached
to the cluster.

Change-Id: I9294e366c3d094a0e532c58b7ef8f16d38db41ee

openstack/senlin-dashboard,openstack/senlin-dashboard,openstack/senlin-dashboard,stackforge/senlin-dashboard,openstack/senlin-dashboard,stackforge/senlin-dashboard,stackforge/senlin-dashboard