glib2 windows: substitute "-" with "_"
glib2 windows: substitute "-" with "_"

It is for "gobject-introspection". "-" is needed to substituted with
"_" for Init_XXX() function.

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