* There's probably a bug, in that things may well break if we don't
   try to create TeX files.  Go through and check for this.

* Create GUI front-end for editing jigsaw files

* Change "sys.exit" in generate-jigsaw.py to exception-throwing -
   this will be needed for when we have a GUI, and it's also more pythonic

* Handle longer text entries by automatically wrapping for jigsaws,
   perhaps
