[CLDMGMT-490] enable sherlock pubslisher in ceilometer-pulgin
	      VM pollster, based on VM instance UUID to fetch metrics instead of instance name.
	      Under nova cell mode, instance name is not consistent ID to specify same VM for nova parent nova cell & compute node.

Change-Id: I9f1b7393f4ca8eca501130843ddc1efcbe20cdea