1. Added more match fields for ICMPv6 and MPLS
2. Fixes to avoid unnecessary warnings in generated code
3. Added the general method Match getMatch() to factories and made unit tests use it
Merge into master from pull request #53:
More java fields (ICMPv6,MPLS), warnings removal from generated code, getMatch() method, unit tests update (https://github.com/floodlight/loxigen/pull/53)