Seeder does not return any NS records

[JeremyRand]

It would be helpful if the seeder returned an NS record, corresponding to the domain name where the seeder is running. This would enable stuff like dig NS seed.namecoin.libreisp.se to work correctly.

[gits7r]

I think this issue is very relevant at present moment as it causes problems with some resolve queries via SOCKS5.
While we are at it, we might also fix a secondary (but not so crucial) problem, that we also don't return any valid SOA with the query: No valid SOA record came back! -- having these two fixed should help our dnsseeds be resolve-able via Tor.

[ss11s]

This fix is important for onion network only new starting nodes, otherwise you must use addnode with a running node in order to be able to join / bootstrap to the namecoin network. Without the NS and SOA return, when the seeders are queried via Tor/Socks5 it does not return any single address of currently running node. Given all NMC dnsseeds use this implementation particularly, it's not possible to get an address, so you must have a running address (pref onion) and use addnode.