This mostly required messing with the STL #includes.

Still builds under gcc 2.95, and won't be built with 3.3 by default
until I've spent more time testing it.

One reason for doing this is that gcc 3.3 seems to generate faster
code from templated functions. Tests so far show that the
gcc3-compiled binary shaves 15-30% off of assign's runtime.

The other reason for doing this is forward-looking. When we end up
getting boss running on FreeBSD 5 or a recent Linux distro, the
compiler is likely to be from the gcc 3 branch.