Updated openstack/openstack
Project: openstack/cinder  c16ca64035e3d8b313e346ac8d175be6fbd8c69d

IBM Storwize: Improve error message

Message "Unable to retype: Volume is replicated." can not really reflect
the reason why retype failed. We need to add additional information to
help user to better understand why retype failed.

Change-Id: If68bb1ba1e72df46fef35394c9ad207ffdeb271b