[gtkada] Gtk.Extra.Plot

[Manuel Op de Coul]

>I don't mind doing this change which seems right to me, but I do care 
about
>understanding these changes, and not making them blindly, with no 
explanation,
>which is probably why your original report was ignored.

I didn't give more information since I thought it was completely
obvious. Strange you can't find it, I've used it with GtkAda 1.2
and noticed it brake when I switched to 2.2.

Manuel