Emphasis test ROM

[rainwarrior]

I couldn't find anything that tests emphasis by itself, so I made a simple ROM to do so. It cycles through the 8 combinations, one per 64 frames on the top half of the screen, one per 8 frames on the bottom half. It should work on NTSC or PAL, there's no special timing going on, just a sprite-0 hit.

The sprite split was necessary do demonstrate an issue with an emulator I was making a bug report on, but if you're trying to write an emulator and sprite split isn't in yet, the behaviour top half of the screen should suffice to test, I suppose.