"use/stage2/net-eth use/net-eth" would be common enough
for installers or livecd images to just get these pulled in
together by a convenient shortcut thus reducing confusion
and chances to just forget one of these counterparts.

This feature intrinsically depends on predictable
ethernet interface names and makes no sense without
those; so it only seems reasonable to bring this
nice package in, huge thanks go to shaba@ of course.

A hint regarding livecd-net-eth is due -- as well as
review and cleanup of live, net, net-eth features
involved in configuring that ethernet for a LiveCD.

This one is also putting an end to an overly long lived hack
named vm-net by replacing it with a bit more generic mechanism.