Added Krush Blokk match 3 game example

Please review and let me know what I screwed up and where! :)

Should only work with `loom use latest --firehose` for now due to the recently merged `OffsetTiledImage` functionality.
You're right, I haven't reviewed the particle classes much after doing a straight port. I'll remove missing functionality (mainly blendmodes). It can be added later on in the C++ version or otherwise.