- After restarting, I realized that I had combined both types of sync
  into one line, when the syncing failed.  This fixes that bug.

- Store sync status directly in the HDD log, to make sure we know
  about it if something fails.  This won't help if the HDD_LOG
  variable is borked, but it'll help with everything else.

- Made sync a function to avoid repeating five lines three times.

- log2ram now requires (cp or rsync) and tee, mount, umount.

From @datenklause
With Type=oneshot, systemd waits until the start action has completed
before it considers the unit to be active, so dependencies start only
after the start action has succeeded. With Type=simple, dependencies
will start immediately after the start action has been dispatched.

thank hardvk0 from armbian forum

no x flag for logr2ram.server

The name of the mount point is now log2ram

Move "Before" to "[Unit]"

Update README.md to correct path to log2ram

This tweak is required to make it run under Ubuntu 16.04