v0.8.1 multiplayer beta

Major

- Multiplayer beta (most likely buggy)

- Endless changes

Minor

- More bugs

- Nerfed a specific boss's health 1500 & 2000 -> 1000 & 1000

- Katana now swings from up to down instead of right to left

- Katana now throws 4 shuriken's instead of 2