webadmin: Fix edit cluster policy for new cluster

When Creating a new cluster the cluster policy data was not saved
because of different view initialization process.

Added a bounding between the clusterPolicyModel in the view and
ClusterModel (which was missing in the 'New Cluster' flow).

Change-Id: I305a71e888e72e35cd40dd1055b6ad22d6111678
Signed-off-by: Ofri Masad <omasad@redhat.com>