A more appropriate wake-up hook.

[Michael Heyns]

A working systemd-sleep hook is included but as per its man page:

Note that scripts or binaries dropped in /usr/lib/systemd/system-sleep/ are intended
for local use only and should be considered hacks. If applications want to be notified
of system suspend/hibernation and resume, there are much nicer interfaces available.

I have searched for "nicer interfaces" but I cannot find a simple or straight-forward bash implementation.
I also don't want to add another dependency unless it's really worth it. Open to suggestions.