Todo:
* Private key file parsing use io.Reader (or the like) - NewReader, NewWriter?
* Tsig generation for replies (request MAC)
* Parsing from strings, going with goyacc and .cz lexer
* encoding NSEC3/NSEC bitmaps
* Failed Xfr trigger nil error

Issues:
* Check the network order, it works now, but this is on Intel??
* Make the testsuite work with public DNS servers
* pack/Unpack smaller. EDNS 'n stuff can be folded in

Examples:
* Test impl of nameserver, with a small zone, 1 KSK and online  signing