No longer passing spurious core reference to main_event_watch.
Fixed a bug with input due to misunderstanding ! vs ~, and changed controller checks to better support multiple button flags |d together; now returns true only if all buttons meet the criteria.
Changed helpers to use RGBA instead of ARGB, because SDL_gfx likes RGBA better. Also added load_image_flipped using SDL_gfx.
Refactor; decided I like 'delete' more than 'destroy'.
Switched main loop over to doubles for improved precision.
Changes to pull in SDL_gfx.
Basic implementation of an animation system, with some test code hacked into game.c