[fix / feature / functional]

Makefile:
	more variables, can now automatically compile files fom src/ into objects in obj/
	also automatically links objects from obj/ into a binary as bin/corridorsnatch.bin
	no more 'stable' or 'debug' targets

.gitignore:
	ignores *.bin files now

main.c:
	window stays on for 10 seconds for testing

engine.h:
	added a missing stdbool.h

engine.c:
	default window resolution is now 854x480 instead of 800x600
	changed from engine_initialise() to engine_initialise(void) to subvert warning (see: http://stackoverflow.com/questions/42125/function-declaration-isnt-a-prototype)