message: Fix broken link
  Also, as a side note, I found this link confusing. I was expecting it to take me to a list of pre-made estimators. Not a definition of what a pre-made estimator is. (maybe the glossary definition should link to a list of pre-made estimators?)
diff: @@ -177,7 +177,7 @@ other features so you can concentrate on your model. For more details see
  An Estimator is any class derived from @{tf.estimator.Estimator}. TensorFlow
  provides a collection of
  -[pre-made Estimators](https://developers.google.com/machine-learning/glossary/#pre-made_Estimator)
  +[pre-made Estimators](https://developers.google.com/machine-learning/glossary/#premade_Estimator)
  (for example, `LinearRegressor`) to implement common ML algorithms. Beyond
  those, you may write your own
  [custom Estimators](https://developers.google.com/machine-learning/glossary/#custom_Estimator).
  