Users can no longer enter 00:00:00:00:00:00 into the mac address field
Fixed interfaces being created with 00:00:00:00:00:00 as a mac address in tests.
Migrate 00 macs as blank
Merge pull request #14 from murrown/church29-MAC_Validation

Migrate 00 mac addresses as blank
Merge pull request #267 from church29/MAC_Validation

Users can no longer enter 00:00:00:00:00:00 into the mac address field