Updating the networking for Gentoo.

The layout and configuration of Gentoo has changed radically and this
update applies the new configuration standard as well as adds a header
to files to warn about the automation in place.

Also removed the logic to detect openrc as it was using logic that was incorrect and there is no longer a way to have a Gentoo system without openrc and baselayout-2 without being almost a year out of date or more.