add improved btGeneric6DofSpring2Constraint, thanks to Puhr Gabor and Tamas Umenhoffer!

improved the new demo testbed (work-in-progress)
add basic Lua demo, import URDF test, STL import, obj import

Demos/SerializeDemo/SerializeSetup.h

@@ -0,0 +1,14 @@
+#ifndef SERIALIZE_SETUP_H
+#define SERIALIZE_SETUP_H
+#include "../../Demos/CommonRigidBodySetup.h"
+
+class SerializeSetup : public CommonRigidBodySetup
+{
+public:
+    SerializeSetup();
+    virtual ~SerializeSetup();
+    
+	virtual void initPhysics(GraphicsPhysicsBridge& gfxBridge);
+};
+
+#endif //SERIALIZE_SETUP_H