Use physical_resource_name as Ref for Instance/AS Group

This allows to distinguish groups by stack when using resource
OS::Metering::Alarm with the rule:
matching_metadata: {
    'metadata.user_metadata.groupname': { 'Ref': 'WebServerASGroup'}}

And add test for AutoScalingGroup Tags

fixe bug #1215840

Change-Id: If3de5c4abddcfb49f711db223a0c1a8c70f3c15a
Merge "Use physical_resource_name as Ref for Instance/AS Group"