IPv6 address literal support

IPv6 addresses represented as 16-element array of (unsigned-byte 8)
ipv6-to-vector converts IPv6 literal address string to vector
vector-to-ipv6 converts vector to IPv6 literal address
refactor format to be slightly less confusing
first cut at IPv6 support for CCL
Merge commit '4f27d08df038871fdf65dcd6460f4d1ce64bf509'