This completely redoes the garbage flags stuff I did before. OOPS. This seems a lot closer to the format, and also exports everything Starfighter has properly.
libpixel (suprisingly) still compiles, but depends on libraries in a very annoying manner that makes EuropaTools hard to compile. Also, I don't like stb_image_write.
Replace it with some hand-done structs and the simpler/faster/better `lodepng`.
