working on Win64 port

[James Lacey]

I just wanted to send a heads-up to the mailing list in case someone else is
working on this so we don't duplicate any effort. I noticed on the status
page that an x86_64 build is only supported on Linux. I just built a new
computer with an Athlon 64 X2 processor so I thought it would be a fun
project in my free time to try to get quake3 to build on MSVC 8 for x86_64.
Since this is a spare-time project, I don't have an estimate for completion
but I did already run into a nasty ICE when building for x86_64 so it looks
like the task will be a little harder than I initially thought.

Later,
James