Support DDNS

Hi!

I've seen some questions go around about this, but mostly old or without a clear answer.

My question is the following - Has CoreDNS been developed to support RFC 2136 Dynamic DNS updates (over UDP)? If not, is there a plan to do that? or if not, is there a reason not to?

We have IOT in bare-metal clusters that we want to provide DHCP and use it to update our self-hosted CoreDNS. If there's a will to support that, I would help implementing this :)

I think we can take some inspiration from external-dns in the way they write to etcd to store entries.