GRAPHITE Prerequisites Documentation, System Issues

[Aaron W. LaFramboise]

I'm happy to see that GRAPHITE it is in trunk now!

I don't see any documentation of prerequisites in install.texi yet; 
perhaps we should add this so users can figure out what they need to do 
to get this framework to work.

In fact, 'grep -i graphite gcc/doc/*' doesn't match anything, so I guess 
documentation is still in progress?

Also, are there any system-specific issues that need to be worked on (eg 
on Windows), or should GRAPHITE and its support libraries pretty much 
work on all host platforms?