We have three groups
adns : the hidden primary bind server
ns : the secondary public authoratitive servers
dns : both of the above
Only the primary server needs to clone the bind config repos and
notify the secondary servers on updates. So the dns_repos and
dns_notify arguments can go into adns.yaml so they're only available
to the primary server.
Only the secondary servers need to know the ip address of the
master/primary server so it can allow itself to be notified by that
IP, and do transfer requests. So dns_master_ipv<4|6> can live in
ns.yaml
This leaves in dns.yaml the one thing both have to agree on, which is
the zones to transfer betwen each other.
Change-Id: Ibd8063e92ad7ff9ee683dcc7dfcc115a0b19dcaa
a2569707fe