Reverted unit test back to original - DDZ zone names are now bidirectionally converted (name <> ll representation) in the OSPF handling layer s.t. skv has always readable names.
Added address_is_ipv4 utility.
Added handling for no ip address case in zone definition (and from OSPF, conversion of :: => no ip). Makes code more compliant with the draft.
Added array_unique method.
Converted the DNS server IPv4/IPv6 address stuff to use DS TLV instead of JSONBLOB.
Added TODO about missing feature (search domains are still transmitted in JSON, even if we don't really have to).