[Coco] Update on new Coco 3 game engine

[Nick Marentes]

Currently, I'm dividing by 2 and the fidelity is good.

I've been experimenting with WAV files on my Amiga and downsampling them 
to see how far I can go before it starts sounding crap.

I found that a divide by 3 (5.243 Khz) still produces acceptable sound 
fidelity for sound effects although not so good for musical tones. I 
won't have music, mainly guns and explosions so this may be good because 
it buys me some more cpu cycles for the game while still maintaining the 
sound.

I'll play it by ear as I go. I can always go up again in fidelity if I 
can afford to.

Nick