Lowprio Wishlist: Allow multiple IP addresses for a printer.

[rewolff]

See also #25. My printer is reachable on a different IP address depending on my location/network connection. So having a "secondary IP address" for a printer would be nice for me. If the printer cannot be reached on the first IP address, try the second. (At work, both will work, at home ONE will work, outside both WIFIs, only the second IP address will work).