message: Fix model zoo documentation link
diff: @@ -135,7 +135,7 @@ above, and you we still need an output labels file.
  To compute mAP in a consistent and interpretable way, we utilize the same 2014
  COCO 'minival' dataset that is mentioned in the
  -[Tensorflow detection model zoo](https://github.com/tensorflow/models/blob/master/research/object_detection/g3doc/detection_model_zoo.md).
  +[Tensorflow detection model zoo](https://github.com/tensorflow/models/blob/master/research/object_detection/g3doc/tf1_detection_zoo.md).
  The links to download the components of the validation set are:
  