private void trace(String s, MouseEvent e) {
		Msg.trace(this, "click count = " + e.getClickCount() + " - " + s);
	}
Places the given plugin at the front of the list

@param p the mouse plugin to prepend
Ghidra/Framework/Graph/src/main/java/ghidra/graph/viewer/event/mouse/VisualGraphPluggableGraphMouse.java