/**
  * Add a model to the list of models that should be included in all cases
  *
  * @param  \Model $model The model to include
  * @throws \Exception When a model is of an unsupported type
  */
 public function addInclude(\Model $model)
 {
     $type = strtolower($model->getType());
     if (!in_array($type, $this->types)) {
         throw new \Exception("Objects of type \"{$model->getTypeForHumans()}\" are not supported");
     }
     $this->included[$type][] = $model;
 }