Added osg::State::popAllStateSets() method to pop all remain StateSet's off

the state stack, thus readying the state object to recieve a new frame.

Removed the state.reset() call in osgUtil::SceneView::cull() as this was
causing problems with stats producing inheritance of state when toggling
stats on.

src/osgProducer/ViewerEventHandler.cpp

@@ -170,7 +170,7 @@ void ViewerEventHandler::StatsAndHelpDrawCallback::operator()( const Producer::C
        
     state.popStateSet();
     
-    state.apply();
+    //state.apply();
 
 }