Added functionality for printing all available directories.  Launch (multiple instances of) vlc without it hogging the command line. Beginnings of ffmpeg concatenations of a directory with video files (files whose names can be alphanumerically sorted to put them in temporal order).
Fixed a bug in the alphanumeric sort...the function now handles stings and tuples without error
Removed an extraneous function
Merge branch 'David_results_script'