Added support for CameraNode's PostDrawCallback.
Added support for CameraNode's PostDrawCallback.


jtorresfabra/osg,marchelbling/osg,openscenegraph/osg,artoolkit/osg,scrawl/osg,scrawl/osg,scrawl/osg,jtorresfabra/osg,marchelbling/osg,tomasthoresen/osg,tomasthoresen/osg,tomasthoresen/osg,openscenegraph/osg,artoolkit/osg,openscenegraph/osg,scrawl/osg,marchelbling/osg,tomasthoresen/osg,artoolkit/osg,jtorresfabra/osg,jtorresfabra/osg,marchelbling/osg,artoolkit/osg,openscenegraph/osg