Make sure that AutoScaling group has it's tag set correctly

At the moment we have to rely on the base classes metering.groupname
and this AutoScalingGroupName is effectively lost.

Change-Id: I6f4c099bde83fba5ad89e43297503943136b717e
Partial-bug: #1373247
Merge "Make sure that AutoScaling group has it's tag set correctly"