Current Steam installations seem to have a much cleaner filesystem
layout on Debian while older ones look quite different.
Older Debian installations ~/.steam/root points to ~/.steam while newer
ones point to ~/.steam/debian-installation and hence BeamMP cannot
find integrity.json. 'steamapps' is at ~/.steam/debian-installation in
newer installations.
On the older installations, 'steamapps' is at ~/.steam/steam/steamapps.
Signed-off-by: Markus Ingalsuo <markus.ingalsuo@gmail.com>
