Rewrites pj in Ruby
Adds a way to access original Perl version of pj

PERL=1 pj

This commit will be short-lived.  Just a fun technique (maybe).
Removes Perl version from pj
Replaces pj link with actual pj script
Replaces pp (xml) with old Perl version
Prefers xprop to xdotool in in-cwd
set-all-facl: makes --user the default

Kept forgetting to specify any permissions.
set-all-facl: refactors run_cmd and print_cmd
set-all-facl: refactors for better var names
set-all-facl: touches non-existent files

Useful for creating files in dirs owned by root (since it will `sudo` as
needed).