Bit fiddling operations with negative fixnums now work.
Remove unportable code of the type va_list d = cs.
Simplify gathering of &rest and &key arguments in compiled code.
growth of the stack and in the way va_arg() arguments can be accessed.
Fix the bytecodes compiler so that it handles toplevel forms properly and
so that it understands LOCALLY.
Split configure.in into configure.in+aclocal.m4 and improve the resulting
tests.