new version of gtk-- drawing widgets

[Jon Trowbridge <trow emccta com>]

I've just made version 0.3a of my Gtk-- drawing widgets (Gtk_Canvas
and Gtk_Plot) available at http://www.emccta.com/~trow/gtk.html.

Besides the usual bug fixes, new features in this version include:
* Easy support for timeouts and idle functions in a Gtk_Canvas.
* More control over GCs built into the Gtk_Canvas class.
* The "current font" in the Gtk_Canvas is now stored inside the "current
  GC", so that gc_save() and gc_restore() will properly affect fonts.
* Added a new sample program: a simple implementation of Life.

Enjoy,
-Jon Trowbridge
 EMC Capital Management, Inc.