[CM] compiling cm 3.9.1 from svn

[anders.vinjar at bek.no]

    >> in src/Scheme.cpp, a symbol s7_NIL is referenced but it doesn't
    >> exist. I had to change it to s7_nil

    B> argh -- this is a bug in my cross-referencer -- I was trying not
    B> to clobber anything used by Rick's code.  I'll put s7_NIL back in
    B> s7.h.

Hi.  I've committed the fixes done in Stefaan's #4 to trunk, so CM/Grace
uses s7_nil and compareNatural() now.

-anders