- Disables panning of the whole scene by mousewheel if the event is not

catched earlier by an item implementing this. Test it at the empty space 
  where the auto button appears in the plot window or on the scaleItems.
  Which element does this panning by default? parents: scene or view?

PlotItem.py

@@ -876,7 +876,9 @@ class PlotItem(QtGui.QGraphicsWidget):
             mode = False
         return mode
         
-        
+    def wheelEvent(self, ev):
+        # disables panning the whole scene by mousewheel
+        ev.accept()
 
     #def mousePressEvent(self, ev):
         #self.mousePos = array([ev.pos().x(), ev.pos().y()])