Consider adding an standalone sample notebook of Facets

[haokanga]

Usage of Facets can be found at the samples such as:
https://github.com/googledatalab/notebooks/blob/master/samples/contrib/mlworkbench/structured_data_classification_police/Predict%20Case%20Resolution%20(small%20data%20experience).ipynb

Given the importance of data visualization, please consider creating a standalone notebook to address best practices and how to use the built-in Facets feature in Datalab.

Besides, please add concrete examples using a sample dataset to explain how to interpret the Facets result, and how to transfer the insight into action items, such as data cleaning or feature engineering.
One possible structure can be:

1. Image of the Facets result
2. Human interpretation
3. The code