2.3 update

tvdb_mp4.ini has new options for some alternate setups. You can now have
the conversion process dump the new files into a different directory
(good for iTunes setups) and preserve the original download. You may
also choose between the mp4 and m4v extensions. Compatible with both
sabToSickBeardwithConverter and postConversion solo runs.
Note - if you disable deleting of the original file, you must specify an
alternative output directory. Without an alternate directory sickbeard
would get confused with the duplicate files.