core : Search VMs based on MAC address

Users should be able to search for VMs from Webadmin-Portal
Search bar using a search query filtering on mac address:

Vms: mac = 00:1a:4a:b4:9b:a8

Change-Id: I0e013038ad19f3750341e8d4156d93de45510d69
Bug-Url: https://bugzilla.redhat.com/1016916
Signed-off-by: Ravi Nori <rnori@redhat.com>