Restrict list of interfaces

[remmelt]

Some virtual hosts have a huge list of network interfaces, pushing the other useful information off the screen. For these hosts, it would be great if we can limit the interfaces shown. The default behaviour can be as it is currently. One of our vms on hyper-v has 18 veth* interfaces...

1. --limit-interfaces 2 seems like a bad idea because we don't know the order of the interfaces
2. --interface eth0 --interface docker0 --interface ... would be fine
3. A config file would be overkill, I guess, especially since it's a per-host setting