fix some btMultiBody URDF conversion issues in ImportURDFSetup

remove various vertex format structures and use GLInstanceVertex from #include "OpenGLWindow/GLInstanceGraphicsShape.h"
btMultiBody::setupPrismatic takes an additional argument to allow a shift of inertia tensor, relative to the joint frame (link frame at q=0)

Demos3/AllBullet2Demos/main.cpp

@@ -193,7 +193,9 @@ void openURDFDemo(const char* filename)
     ImportUrdfSetup* physicsSetup = new ImportUrdfSetup();
     physicsSetup->setFileName(filename);
     
+
     sCurrentDemo = new BasicDemo(app, physicsSetup);
+	app->setUpAxis(2);
     
     if (sCurrentDemo)
     {