have top-level Makefile.nmake call Makefile.nmake's in subdirectories.
Build plugins, and build generated source (lex, yacc). The only thing we
can't build is register.c; I need to re-work the top-level Makefile.nmake
because it lists object files, not C files, which make-reg-dotc needs.
svn path=/trunk/; revision=1608