implement equivalent of BIND's transfer-source and notify-source

[anon]

Please implement equivalent of bind's "transfer-source" and "notify-source" for both IPv4 and IPv6. Logic behind this would be:

transfer-source <ipv6addr or ipv4addr>,... notify-source <ipv6addr or ipv4addr>

transfer-source would use addresses in given order, if first fails, it goes to the other one, etc...

this should to be specified either globally or per-zone using domainmetadata.

[peter]

I believe r2616 covers per-zone transfer-source