[MLton] Emacs mode for editing ML Basis files

[Matthew Fluet]

> > I think it's worth putting this code in the SVN, for easier future
> > editing, so you don't have to muck with the wiki.  It's at
> > doc/esml-mlb-mode.el, and can be accessed with ViewCVS at
> > 
> >   http://mlton.org/cgi-bin/viewsvn.cgi/mlton/trunk/doc/esml-mlb-mode.el?view=markup
> > 
> > I also updated the wiki to point there.
> 
> Ok. Regarding the directory, I think that something like ide/emacs
> might be good for possible future development (e.g. ide/eclipse).

I left it as doc/emacs.  Since directories and files are movable with
history, I'm less concerned about reorganizing in the face of future
developments.