support keras fit history in estimator's train_and_evaluate

[karterotte]

User Story

I want to hold a record of the loss values and metric values during training, like keras History object: https://www.tensorflow.org/api_docs/python/tf/keras/callbacks/History https://keras.io/guides/training_with_built_in_methods/

Detailed requirements

I have to decide saving or not models depends on it's metrics(maybe lastest one).

API Compatibility

hb.estimator.train_and_evaluate

Willing to contribute

Yes