DNS 0x20 https://tools.ietf.org/html/draft-vixie-dnsext-dns0x20-00
is a way to add more randomness into queries to make spoofing tougher
this implementation provides up to 32 bits of randomness to QNAME,
which is more than enough for most names (it is possible to add a
maximum of 1 bit of entropy per alphanumeric character, so it's not very
efficient with shorter names)

fixes #27

libuv doesn't do connected UDP sockets, so we can't get ICMP unreachable
otherwise

by default it blocks queries to private zones, can be extended to match anything in the query content (i.e. water torture style attacks)

before root hints were hardcoded to the resolver,
now they are present in form of a cut in the resolution
context, and the modules can add/remove/replace them
on the fly