[ut2003io] Screenshots, not so important, but nice....

[Ryan C. Gordon]

Talking with some people, this seems to be a bug in the latest Nvidia 
drivers...I'm on 3121 (or whatever) and it's working fine here...others 
are reporting similar results.

So I assume this will fix itself in the future if you don't want to 
downgrade your drivers.

Someone also noted that running the game in windowed mode makes 
screenshots work, too.

--ryan.