Bug fix: targets of camera or lights are now exported correctly

Exporters/3ds Max/Max2Babylon/Exporter/BabylonExporter.cs

@@ -320,6 +320,11 @@ namespace Max2Babylon
                 case Autodesk.Max.IGameObject.ObjectTypes.Light:
                     babylonNode = ExportLight(maxGameScene, maxGameNode, babylonScene);
                     break;
+                case Autodesk.Max.IGameObject.ObjectTypes.Unknown:
+                    // Create a dummy (empty mesh) when type is unknown
+                    // An example of unknown type object is the target of target light or camera
+                    babylonNode = ExportDummy(maxGameScene, maxGameNode, babylonScene);
+                    break;
                 default:
                     // The type of node is not exportable (helper, spline, xref...)
                     hasExporter = false;