Removed SFML framerate capping.
Now each entity has a UID.
Now, it's clear that every controller is assigned to a single player.
Made public interfaces more complete for future networking system.
Improved joystick support by resurrecting old JoystickController.
Added networking support. Press 'K' to create server, 'J' to join localhost.
Added network_controller.cpp to optimized build system (mk shell script).
Fixed drawing order (especially when joining from network).