Added ref_ptr<> to quieten down Coverity
Added ref_ptr<> to quieten down Coverity

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