Live Migration Via Server-Manager Fails.

Closes-Bug: #1350458
Issue:
1. on installation via SM, volumes created are going to error state
2. live migration via SM is failing in chown nova:nova <global-dir>

Fix:
1. before cinder-config, check if all OSDs came up. if not, then exit
    without configuration
2. rectified the check for <global-instance-dir>
Test:
1) install complete all nodes with storage support.

Found some more issue.
1. restarting cinder-volume before ceph cluster is full-up, causes RBD
  driver to be uninitialized and future volumes created will go to error
  state.
  FIX: So added check for all OSD to be up before storage-openstack
   configuration and relevant changes to contrail_storage.pp
2. missed a check for RETVAL of command while live-migration configuration

===============
Fix check for directory existance.

Change-Id: I66d42ac37b80b784557781ec8404aa3275244f05