Spaceship-toy

Fly around and shoot objects (or your own bullets, or yourself).  
Engage the tractor beam to manipulate objects at a distance.  
Writhe in existential despair as you realize that the entire 
universe is a topologically-toroidal prison populated only by 
you and inanimate objects.

Todo
	internal cleanup
		replace lots of mallocs and frees with object pools
		rename Pair struct and add more functions to manipulate them
		replace gameObjects table with a few more specialized tables
		ensure that collision code has no sign errors
	features
		new kinds of weapons
		allow user to select different weapons
		make "obstacle" and "ship" vulnerable to damage and "killable"
		enemies that actively attack you
		
Future directions
	sound for thrusting/shooting/collisions/explosions
	hot seat multiplayer
	splash screen
	settings screens
		control mapping
		video settings
		audio settings