v1.1

Hey everyone! This is a small post-release balancing and polishing update.

• Fast enemies are slower
• Levels are 25% smaller
• More shotguns spawn
• Zombies/ghosts are deaf
• Guns have less recoil
• Spooky track doesn't play for ghosts
• Added sound effect for gun swapping
• Removed zombie heads
• Added a version number to the sidebar

Also, the source code is now available.

Thanks for playing!