* properly handle .mount unit state tracking when two mount points are stacked one on top of another on the exact same mount point.
Features:
+* support units generated by a generator and placed in /run/systemd/system/; the directory is
+ currently ignored because it is empty before the generatores are executed
+
+* let 'systemctl reboot' called as non-root talk to logind instead of systemd, to get polkit
+ system policy in the loop of privilege checking, so normal users can possibly use /sbin/reboot
* Possibly, detect whether SysV init scripts can do reloading by looking for "echo Usage:" lines