Support for connecting to control port over ipv6

[arkadiyt]

Right now the --interface option only supports connecting to ipv4 addresses - it would be nice if I could connect over ipv6 as well.

The use case is that I'm deploying Tor on https://fly.io and they connect applications together over ipv6:
https://fly.io/docs/reference/privatenetwork/

To avoid running Nyx / the control protocol over the public internet I'd like to deploy Nyx in a container which I ssh into, and that container connects to my Tor instance over ipv6.

Thanks,