Updated the Lua wrapper code for modules to account for cases where the module's instance is removed from memory completely and recreated during the program's lifetime.

src/modules/physics/box2d/Physics.cpp

@@ -33,6 +33,11 @@ namespace box2d
 
 int Physics::meter = Physics::DEFAULT_METER;
 
+Physics::Physics()
+{
+	moduleType = M_PHYSICS;
+}
+
 const char *Physics::getName() const
 {
 	return "love.physics.box2d";