UPDATE! Tiny Bot Mode and some bug fixes

Hi there!

With this update we changed some stuff.

New
- Singleplayer Bot Mode (Bot Attack)
-- Collect Bullets and survive as long as you can without touching the moving enemies!
- New Weapon -> Crossbow
- Lobby Badges

Changes
- We changed some bullet effects to fit the current weapon style

Fixes
- Fixed the lightning powerup (Coop-Mode)
- Fixed the dash sound (Coop-Mode)