Update on supported Tetzle puzzles

It actually turned out to be a lot easier to support current puzzles than I was anticipating. I solved the bevel issue by simply disabling bevels for puzzles created before piece-based bevels were added. Plus, the file format had not changed as much as I had thought, so they were much simpler to convert than I expected. Current puzzles will still be supported in the next Tetzle after all!