Changes:
* Fixed serious bugs (depends on GC)
* Support GTK+-2.10 and the latest version of each libraries.
* Don't include Ruby/GStreamer and Ruby/Libgda. We cancel to
support Ruby/GStreamer and Ruby/Libgda.
* Cancel to support ruby-1.6.x and GTK+-2.4 or earlier.
Ruby-GNOME 2 is a set of Ruby language bindings for the various
application development libraries included with the GNOME/GTK+
environment.
Ruby/ATK is a Ruby binding of ATK-1.0.x or later.