Allows to copy dns.name.Name objects
In LOC, deal with 0 values for size, horizontal precision, and vertical precision.
Merge pull request #57 from bastiak/master

Allows to copy dns.name.Name objects
Responses to messages signed with TSIG were broken.
Do not put back an unescaped token.
overhaul test system
Add dns.ipv6.is_mapped(); Reverse IPv6 mapped IPv4 into v4 space
Add dns.rdtypes.ANY.DNSKEY.flags_to_text_set()

Map DNSKEY RR flags bit array to human-readable names.