fyi: using iTerm COMMAND_MODE should be unix2003

[Stephen Bannasch]

I was getting this error re-building mlvm on MacOS 10.5.8.

   ld reports the following error rebuilding libjava.dylib:

     libfdlibm.i586.a, archive has no table of contents

ar (the archive tool) was not building the catalog file for the archive because the environmental variable COMMAND_MODE was set 
to 'legacy'.

This occurred because I recently switched from the Mac OS X Terminal program to iTerm because of iTerms much better handling 
ofcolored and styled fonts.

Without another action COMMAND_MODElagacy when starting up a console shell on Mac OS X using iTerm.

I think most people use Terminal.app in Mac OS X so aren't affected by this problem.

In any case I updated my mlvm build script here: http://gist.github.com/243072 to change the COMMAND_MODE to unix2003 if it is 
set to legacy

references:
http://old.nabble.com/Why-ar-doesn't-call-ranlib-on-Mac--td22319721.html