Call Graph Generator

[Ben Elliston]

   I could show it on tk window if tcldot worked with the old tcl/tk
   version that sourcenav uses. :( When you guys finish porting that to
   tcl8.3 we can make this into another navigator window!!!

Very nice!  I think this would be a nice contribution to S-N, even if it's
just a tool that emits the dot files.  As for how it could be included in
the product, I'll leave that up to the S-N team to contemplate.
Ben