Use hop limit instead of ttl for method and member names.
- Add the Ipv6Repr and Ipv6Packet structures to the wire module - Add basic tests for the new structures - Update IpRepr to include the Ipv6 variant
- Add links to the Addressing Achitecture RFC where appropriate - Add comments to functions where appropriate
- Add the ipv6 feature - Ensure a travis build with the ipv6 feature enabled. - Add the necessary infrastructure to wire for ipv6 support. - Ipv6Address - Ipv6Cidr - Add Ipv6 Address and Cidr parsing to parsers - Add basic tests.