Look for system.Xwinrc in SYSCONFDIR/X11 (usually /etc/X11)
Rename sample system.Xwinrc file not to have a X11R6 path in it's name
Add makefile install rule for system.XWinrc
Signed-off-by: Jon TURNEY <jon.turney@dronecode.org.uk>
Reviewed-by: Colin Harrison <colin.harrison@virgin.net>