* extconf.rb: Follow mkmf-gnome2.rb changes. Support MSVC++.         compile to set GTK_BASEPATH as the environment variable. * sample/rose.rb, testlibart2.rb: Work on mswin32/mingw.
* extconf.rb: Follow mkmf-gnome2.rb changes. Support MSVC++.
        compile to set GTK_BASEPATH as the environment variable.
* sample/rose.rb, testlibart2.rb: Work on mswin32/mingw.


benolee/ruby-gnome2,benolee/ruby-gnome2,benolee/ruby-gnome2