Add VM list filtering by tag

Uses same method as state or node filtering, rather than altering how
the main LIMIT field works.

node-daemon/pvcnoded/MetadataAPIInstance.py

@@ -180,7 +180,7 @@ class MetadataAPIInstance(object):
         client_macaddr = host_information.get('mac_address', None)
 
         # Find the VM with that MAC address - we can't assume that the hostname is actually right
-        _discard, vm_list = pvc_vm.get_list(self.zkhandler, None, None, None)
+        _discard, vm_list = pvc_vm.get_list(self.zkhandler, None, None, None, None)
         vm_details = dict()
         for vm in vm_list:
             try: