beta 0.3

additions

• added slabs, stairs, quarter blocks, and diagonal slabs
• added wall jumping
• background is now a light gray
• now displays how many levels you've completed and saves it

fixes

• adjusted a bunch of variables to scale player movements with the level dimensions properly
• fully fixed collisions
• you won't notice it, but i made the level size smaller (20x15 vs 24x18) because the original was going offscreen
• still adjusting the whitespace chance so more levels can be completed