Added better handling of OSG_TEXT_INCREMENTAL_SUBLOADING env var.
Added better handling of OSG_TEXT_INCREMENTAL_SUBLOADING env var.



stmh/osg,ghub/osg,ntoand/osg,XiaoCC/osg,koshman86/osg,artoolkit/osg,stmh/osg,stmh/osg,omega-hub/osg,stmh/osg,XiaoCC/osg,omega-hub/osg,koshman86/osg,artoolkit/osg,omega-hub/osg,ghub/osg,XiaoCC/osg,XiaoCC/osg,ntoand/osg,ghub/osg,koshman86/osg,XiaoCC/osg,ntoand/osg,artoolkit/osg,ghub/osg,koshman86/osg,stmh/osg,omega-hub/osg,ntoand/osg,artoolkit/osg