How might I add a shutdown button in DockBarX? I see from the below image (from http://www.omgubuntu.co.uk/2011/02/window-switcher-dockbarx-adds-media-player-buttons-dock-helpers/)
that I seem to be able to have a "start menu" in dockbarx? How can I do that? I think it will have a shutdown button in there already

