Ethernet's untagged VLAN notation updated. Match.Builders created from exising...

Ethernet's untagged VLAN notation updated. Match.Builders created from exising Matches will only remember parent Match's MatchFields if the new builder is not modified (not very useful IMHO). MatchUtils.java added to create a new builder from and existing Match and retain all the MatchFields unless explictly overwritten with the new builder.