An rpg made in golang using the pixel library

improvement ideas:

• sound volume should be adjustable in the config file
• support of multiple levels instead of a single level
• should the player be included in the entity package since it shares so many properties already? it could be like the spawner, a superset of entity
• a cool ui for the player
• rename entities "actors?"
• use the command pattern for controller events
• use more events in general, register for events and what not.
• perhaps I should make "engines" owned by a central game object (higher that world) and these engines are responsible for managing messages between components. for example, gui should hold a reference to the window class, but should instead register themselves with the relavent events they would like to know about.