rc.shutdown :
Main unmount code block changed code that reverses the
mount order to using tac instead of the long sed pipe.
Using /proc/mounts directly has the advantage to easier
handle special chars like spaces in directory/filenames,
since the /proc/mounts file uses escaped ascii values.
Variables further down also get piped through echo -e and
double quoted for such cases.
Unneeded double quotes and tr "\n" " " deleted.