Code cleanup and refactor. about spacegame HOT 4 OPEN

Move all aux types and hook types into spacegame.core.

from spacegame.

Centralize adding and removing of objects from the game environment into spacegame.core.handler. In fact, anything that directly modifies the environment should probably go in core and simply be called by modules.

from spacegame.

Need to clean up integration tests -- parameter validation should be handled by a helper function.

Consider splitting modules into modules and commands -- commands would contain the actual command definitions while modules would contain all the logic. Alternatively, put the logic in core. Point being -- separate the API from the implementation (woah there Java!)

from spacegame.

Moving this out of 0.3.0 because it's a large, unfocused task. Going to refactor as I work on new/existing features.

from spacegame.