Clean up observer_ptr<> and removed the eronous casting of ptr in objectDeleted.
Clean up observer_ptr<> and removed the eronous casting of ptr in objectDeleted.


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