I was using fvwm-root because it was able to retain pixmap in some X
property for use by some programs. These days are gone and programs
are now using ARGB visual and the compositor. Let's switch to simpler
hsetroot.
This is derived from my Awesome configuration. Still a lot to do from
a WM perspective. The organization is a bit different and I am giving
it up on the per-display systemd units as it does not really work due
to the fact we only have one user DBus and one environment.
