RFC2845
https://github.com/redwyvern/ddns-dnssec-nsupdate
https://github.com/jodrell/pnotify
https://github.com/fln/ddnsadmin
https://github.com/rthalley/dnspython/blob/master/dns/tsig.py
https://github.com/awslabs/route53-dynamic-dns-with-lambda
https://github.com/rafaelmartins/dnsimple-dyndns
https://developer.dnsimple.com/libraries/ https://github.com/dnsimple/dnsimple-node https://github.com/aetrion/dns_erlang