Added ParticleEmitters to Enemies

-Enemies now release particles when you shoot them
-They share ParticlePools with the Blocks
-Also began improving aiming system
-Fixed the issue with UFO blocks
Improved player animations

-Added an appearance sound effect
-Added an explosion effect (a white ring that expands)
-Moved pygame.display.flip() out of GameState and into its subclasses
Merge branch 'master' of https://github.com/CorundumGames/Invasodado
Compressed the graphics

-They're now much smaller
Added some utility functions to config.py

-Abstracted away the loading of sound, music, and graphics
-Also removed GameState.fps_timer and put it in config
Merge branch 'master' of https://github.com/CorundumGames/Invasodado

Conflicts:
	core/config.py
	game/settingsmenu.py