Wall Placement Rewrite and Level Counter

This isn't a huge update, but it brings a couple of changes (along with getting rid of the April Fools' Day sound effects, I'm sure those were getting on your nerves). Most notably, the level counter! This has been a fairly requested feature for a while now, and I got around to adding it this update. The color of the level counter's text changes when you complete a level, turning fully from green to red when you reach Floor 100. Don't think you're going to make it there, but I never know! Go for it if you want.

The other changes were to wall placement, meaning no edge cases where walls won't look right/will let you exit the map. I tried fixing the existing system of checking specific tiles around the wall to determine placement, but it was a mess and difficult to work with, so I decided upon a new system where it looks at all of the adjacent tiles and matches them up to walls using hardcoded rules based off of if each tile is a ground or wall (counting out of bounds tiles as walls even though they're not solid). Another big thing that saved me the time of making a bunch of new tiles was my fallback system. I decided that if a tile's surroundings didn't match any of the given combinations, it would default to being a floor tile and force the tiles around it to update to accommodate said change. That helped a ton, and ended up being the change that actually fixed the edge case problems rather than just making the system easier to use.

Anyway, hope you enjoy the update! I'm hoping to add more content and features now that procedural generation is done, and hopefully turn it into more of a roguelike experience. If you have any suggestions for features, feel free to leave a comment and let me know!