Added RemoveLoadedProxyNodes pass to Optimizer, set on by default at present.

include/osg/NodeVisitor

@@ -20,24 +20,25 @@
 
 namespace osg {
 
-class Geode;
 class Billboard;
-class LightSource;
+class ClearNode;
 class ClipNode;
-class TexGenNode;
+class CoordinateSystemNode;
+class Geode;
 class Group;
-class Transform;
+class Impostor;
+class LightSource;
+class LOD;
 class MatrixTransform;
+class OccluderNode;
+class PagedLOD;
 class PositionAttitudeTransform;
 class Projection;
-class LOD;
-class PagedLOD;
-class Switch;
-class Impostor;
-class ClearNode;
-class OccluderNode;
+class ProxyNode;
 class Sequence;
-class CoordinateSystemNode;
+class Switch;
+class TexGenNode;
+class Transform;
 
 /** Visitor for type safe operations on osg::Nodes.
     Based on GOF's Visitor pattern. The NodeVisitor 
@@ -222,6 +223,8 @@ class OSG_EXPORT NodeVisitor : public virtual Referenced
         
         virtual void apply(Group& node)                     { apply((Node&)node); }
 
+        virtual void apply(ProxyNode& node)                 { apply((Group&)node); }
+
         virtual void apply(Projection& node)                { apply((Group&)node); }
 
         virtual void apply(CoordinateSystemNode& node)      { apply((Group&)node); }