message: Slightly update the keras.Model docstring.
  Adding some reference to the guide for using the Model once its created.
diff: @@ -137,6 +137,13 @@ class Model(network.Network, version_utils.VersionSelector):
  model = MyModel()
  ```
  +
  + Once the model is created, you can config the model with losses and metrics
  + with `model.compile()`, train the model with `model.fit()`, or use the model
  + to do prediction with `model.predict()`.
  +
  + Checkout [guide](https://www.tensorflow.org/guide/keras/overview) for
  + additional details.
  """
  def __init__(self, *args, **kwargs):
  