fix for service no longer running at shutdown
fix for service no longer running at shutdown

As suggested by:
https://bbs.archlinux.org/viewtopic.php?id=188858
http://unix.stackexchange.com/questions/39226/how-to-run-a-script-with-systemd-right-before-shutdown
https://bbs.archlinux.org/viewtopic.php?id=192160
Breaks being able to run backup straight away with "systemctl start"

designondemand/shutdown-backup