glib2: use $, instead of rb_output_fs for portability
glib2: use $, instead of rb_output_fs for portability

GitHub: refs #117

Reported by Marvin Gülker. Thanks!!!

kitachro/ruby-gnome2,kitachro/ruby-gnome2,kitachro/ruby-gnome2,kitachro/ruby-gnome2,kitachro/ruby-gnome2