Chat Vs Streamer Mode

Added a new mode: Streamer vs Chat

• Let the chat battle against the Streamer
• With the new command "!a" the chat can attack the streamer for a place in the leaderboard!
• Every 30 seconds, the streamer will fight back against their viewers with a powerful blow!

Other changes:

• You can select the game mode from the configuration page
• Projectiles have a target so they can't miss.
• Streamer can't play on Boss Fight Mode, but it can play on Platforms Mode.
• When a chat avatar get's defetead, a new message in the chat will make them appear again with full HP.