Build with Visual Studio & MSVC

Just for fun, I went through PostgreSQL 8.1 and did a complete build
using Microsoft's C and the latest Visual Studio.

With a few minor tweaks, everything compiled with no errors.

My assumption is that because PostgreSQL is a UNIX/Linux-centric project
(and gcc/gdb centric), this really isn't of much interest to anyone.

So other than this e-mail, I don't plan to do anything with this except
for my own amusement.

If I'm wrong, and there is some real interest in supporting MSVC, let me
know, and I'll put some work into cleaning it up and making patches out
of it, etc.