Update v0.2

The game has been updated to version 0.2. Here's what changed since version 0.1:

• The game now runs in 60fps!
• Zombies now come in waves.
• Spread-increase pickup items no longer appear until the player has three pellets.
• Updated the game font and game over screen.
• Pickup rarity now increases the more you collect them.
• Pellets now make a sound upon impacting the zombies.
• Miscellaneous balance improvements.