Enable pixel caching for nodes (should yield better performance)

MaterialGraphProject/Assets/GraphFramework/SerializableGraph/Editor/Drawing/Drawer/NodeDrawer.cs

 
             leftContainer.Add(m_ControlsContainer);
             m_CurrentControlPresenter = new List<GraphControlPresenter>();
-
-            usePixelCaching = false;
         }
 
         private void AddControls(GraphNodePresenter nodeData)