Prevent AGH from responding to traffic on certain interfaces (e.g. wan*)

[af3556]

It would be handy to have a interfaces option that behaved similarly to the current bind_hosts but caused AGH to respond only on the given interfaces (ideally supporting glob expressions) rather than a specific IP. In addition or instead, having an exclude_interfaces option to prevent AGH from offering services on the given interfaces would be useful.

I have a local network with a small number of VLANs, all of which I'd like to have AGH serve; I do not want AGH listening on the WAN or remote tunnel interfaces. dnsmasq makes this configuration easy, by way of having both interface and except-interface options; in my case I use interface for my lan*, and except-interface for wan* and tun* interfaces. This keeps everything working when I create new VLANs and otherwise forget to update dnsmasq ;-)

The current implementation bind_hosts requires me to hard-code my current network addressing, and remember to update it.
Even an "exclude interfaces" option here would be helpful: bind_hosts could be set to 0/0 and an exclude_interfaces option of wlan*,tun* reject traffic from those interfaces.