Reworked the TextureObjectManager singleton so that it no longer reconstructed itself once deleted, and added checks to against a null manager to prevent calling code crashing.
Reworked the TextureObjectManager singleton so that it no longer reconstructed itself once deleted, and added checks to against a null manager to prevent calling code crashing.


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