Use param file names for naming original files

As suggested by @joshmoore in https://github.com/ome/scripts/pull/39, the figure scripts (and Make_Movie script) don't use the user-supplied file name to write local files, but only as the name of the uploaded original file.

This is safer, since it's only used in the DB, not in any paths etc.

To test:
 - Run Make_Movie script, and one of the others (same change to all) choosing various strings for Figure or Movie name. Check name after creation.