New service alongside phonebox. Boxes get a random 6 digit number
(100000-999999) signed by the machine's yggdrasil key. A serf gossip
cluster on yggdrasil port 7946 exchanges the signed records;
phonebox-sync verifies key -> address derivation and the signature and
writes the number -> address map to /run/phonebox/numbers for the
asterisk dialplan. Any yggdrasil node running the service can reach any
other; clan-core's ygg-input filter is opened for SIP, RTP and gossip.
Includes a two-node VM test proving directory convergence and a call
over yggdrasil. The existing phonebox service is untouched.
kurogeek
f398daacb5