Rebuilding source

[Matthew Fluet]

I (finally) got the x86-backend to a stable point and I've been trying to
itegrate it with the mlton-20001004 version.  Copying and updating all the
source files went fine.  I've just gotten a little turned around regarding 
the new directory structure and which makefiles to call with what.
Really, I just want to know where to call  make nj-mlton  and where to get
the mlton shell-script file set up correctly.  I know that
/src/mlton/Makefile has a nj-mlton rule, but I keep getting a call to
mlton which I'm not expecting.