`tf.contrib.data.padded_batch_and_drop_remainder()`.
*   `tf.estimator`:
    *   `Estimator`s now use custom savers included in `EstimatorSpec` scaffolds
        for saving SavedModels during export.
    *   `EstimatorSpec` will now add a default prediction output for export if
        no `export_output` is provided, eliminating the need to explicitly