Removed build

Removed a builded jar
Replaced GamePlayer with GameUser

Also there is now a new class called User. GameUser is a subclass,
extending Users functions
Reformat code
Removed .gitignore
Added PlayerJoinEvent handler
Added interface for arenas.

Arenas should load itself at specific locations and self remove.
Added ingame role for GameUsers.

Also added a new class to handle the online gamers.
Added more method signatures for games.
Reformate code
Added class for user handling

Also added a teleport method for users. Added a global state for users.
Added ideas for custom inventories.

These inventories should be setup via configs.
Added class to display scoreboards.