Updated to v0.5.3

Sprites! Sprites for spikes and slimes (formerly unassuming red circles) have been added. Hitboxes for slimes have been adjusted accordingly, as well as a bit of the layout (due to the slimes being larger than the circles they used to be). Wow, pixel art is hard!

I've also adjusted a setting that should get rid of the "blinking" sort of effect you might've seen on the platforms. This comes with its own issues but I think it overall looks better.