Update #1: Hold me...

My first update.  I added a few convenience features today. Firstly, you can now save all the generated sprites at once.  The are all saved to a single .png at the moment, but I might work on allowing a zip of small .pngs.

I also added the ability to 'hold' sprites, which prevents them from being generated over during the next run.  You can hold sprites through multiple runs, and then save either the entire set, or just the held sprites.

That's all for today. I think I'm going to work on some palette handling features next, but I'm open to suggestions.