Added standard constructor with just scene and name for KRModel and KRCollider.

Implemented KRNode::createNode, to create nodes declared in KrCreateNodeInfo structs.
Added stub function, KRNode::update to update node attributes from a KrNodeInfo struct.

kraken/KRModel.h

@@ -49,6 +49,7 @@ class KRModel : public KRNode
 public:
   static void InitNodeInfo(KrNodeInfo* nodeInfo);
 
+  KRModel(KRScene& scene, std::string name);
   KRModel(KRScene& scene, std::string instance_name, std::string model_name, std::string light_map, float lod_min_coverage, bool receives_shadow, bool faces_camera, Vector3 rim_color = Vector3::Zero(), float rim_power = 0.0f);
   virtual ~KRModel();