Adding Ruby support to Source Navigator

[Ben Elliston]

Yo Mo,

   Well, are you going to be around to help keep it working? I don't know
   that would have a problem with adding support for ruby, I just want to
   make sure we don't end up with an abandoned parser. I know Ben was
   thinking about what changes would be needed to move the syntax
   highlighter out of the core, but he would know more about that.

I've already started -- I have the configury in place to build the syntax
highlighters as shared libraries with libtool.  The next step is to just add
in the hooks to load these libraries with Tcl's "load" command at start-up.

I'm trying to decide whether all libraries matching a specific pattern (say,
"*high*.so" should be loaded, or whether they should be named explicitly in
the configuration file.  Thoughts?

At any rate, this'll be a vast improvement.

Ben