Core: cleanup.

*remove some garbage
*little bit moore const func
*fix process of args in vmap3_extractor

src/server/game/Entities/Object/Object.h

@@ -407,11 +407,11 @@ struct Position
 
     Position::PositionXYZStreamer PositionXYZStream()
     {
-        return Position::PositionXYZStreamer(*this);
+        return PositionXYZStreamer(*this);
     }
     Position::PositionXYZOStreamer PositionXYZOStream()
     {
-        return Position::PositionXYZOStreamer(*this);
+        return PositionXYZOStreamer(*this);
     }
 
     bool IsPositionValid() const;