Figure out what to do with /media/fat

[amstan]

Essentially: pacman should have no right to put anything in /media/fat.

It's against sane packaging hygiene.

It carries the danger of the user modifying stuff managed by pacman, leading to errors come update time.

Perhaps pacman provided files that are read by MiSTer should go in somewhere like /usr/lib/mister/ and somehow mounted readonly to a view (which combines both the user's files and the system-managed read-only files).

Perhaps use /media/usb for user provided files?

# /etc/fstab

/usr/lib/mister/   /media/fat               none  defaults,bind 0 1
/var/mister        /media/usb               none  defaults,bind 0 1 #folder writable by people in the mister group

# optional
/home/alex/misterstuff        /var/mister               none  defaults,bind 0 1

Bonus points: modifying mister binary (which is not too hard to for us to have a patch to and compile) to read directly from /usr/lib/mister and /var/mister without doing any bind mounting. This, while neater, is scary because we'd be moving away from conventions that upstream mister does. Some other scripts FWIW might break.