Add Example of Using Spark with skflow to Easily Scale

[terrytangyuan]

This sparkit-learn package recently came out that utilizes Spark to scale scikit-learn and aid GridSearch. https://github.com/lensacom/sparkit-learn

Since skflow has a sklearn-like interface, it might be a good idea to show an example of using sparkit-learn to scale skflow with minor changes.

Blogpost can be found here: https://databricks.com/blog/2016/02/08/auto-scaling-scikit-learn-with-spark.html

PRs are welcomed for this.

[ilblackdragon]

@terrytangyuan Can you move this FR tensorflow/tensorflow with may be updated details about existing libraries around TF and Spark?

[terrytangyuan]

Closing now since someone submitted an issue at sparkit-learn repo.