Update server and client communication in game simulator

The server (game_server.py) and client communication (overcooked_gui.py) now uses the WebSocket communication protocol. In setup.py, the 'requests' module was added as a new requirement. The game simulator now waits for a player to be ready before starting, stops a game environment if no step is taken within a minute, and pauses or unpauses a game environment. Player actions are now handled based on a new 'Action' type. The server also now handles several client types that can send messages.