Add most of LegoObjectFactory (#365)

* push changes

* push changes

* fix

* Update legoracecar.h

LEGO1/act3actor.h

@@ -3,7 +3,7 @@
 
 // FIXME: Uncertain location. There are three vtables which eventually call this
 //        class' ClassName() function, but none of them call it directly.
-class Act3Actor {
+class Act3Actor : public MxCore {
 public:
 	// FUNCTION: LEGO1 0x100431b0
 	inline virtual const char* ClassName() override