- Use some simple #define's at the top of the files for proc -> thread
changes instead of having lots of needless #ifdef's in the code.
- Don't try to use struct thread in !FreeBSD code.
- Don't use a few struct lwp's in some of the NetBSD code since it isn't
in their HEAD.
The new diff relative to before KSE is now signficantly smaller and easier
to maintain.