Added new osgGA - GUI Adapter library submitted by Neil Salter. This will

replace the current GUI adapter code inside osgUtil.

src/osgGA/GUIEventHandlerVisitor.cpp

@@ -0,0 +1,9 @@
+#include <osgGA/GUIEventHandlerVisitor>
+#include <osgGA/GUIEventHandler>
+
+void osgGA::GUIEventHandlerVisitor::visit(osgGA::CompositeGUIEventHandler& cgeh)
+{
+    for(int i=0; i<cgeh.getNumChildren(); i++){
+        cgeh.getChild(i)->accept(*this);
+    }
+}