ANN: Dnstap telemetry agent supports both unicast and multicast

[Fred Morris]

I updated both ShoDoHFlo and Rear View RPZ (https://github.com/m3047) to
consume UDP telemetry instead of connecting directly to the Dnstap unix
socket for greater flexibility and to support many-to-one, one-to-many,
and many-to-many.

Without a doubt, the most-viewed sourcefile in all of the projects I
have on GitHub is shodohflo/examples/dnstap2json.py
(https://github.com/m3047/shodohflo/blob/master/examples/dnstap2json.py)
so I bowed to the wisdom of the crowd and based the new Dnstap Agent
(shodohflo/agents/) on it. This means that I updated it to support
multicast, and it will get some love from here on out.

If shodohflo/agents/dnstap_agent.py or dnstap2json.py itself don't suit
your payload needs, you are of course welcome to subclass dnstap2json.py
yourself.

I couldn't do it without BIND! Cheers...

--

Fred Morris, internet plumber
http://consulting.m3047.net/pfs-why/