Added preliminary album art exporting, making use of Songbird's "primaryImageURL" property.
This is still done via text files, but samples of how to use it are available in the comment section.
It is *NOT* perfect, but I will hopefully figure out the problems. Feedback would be nice.

Fixed a problem where the text files were not cleared when Songbird was shut down.

Currently supports three text files and exports only the useful information available about tracks.

Does *NOT* handle album art as I'm uncertain how that could be incorporated with current Samurize plugins.