Document how to use a Spark shell

[timrobertson100]

I think a good addition to the tutorials would be how to use kubectl to start an N-sized cluster for running a spark-shell.

(It would be especially good to see a set of recipes that bring up HDFS, Hive, Spark History server, and some form of gateway machine on which you can then run spark-shell similar to a Cloudera set up)

[razvan]

Yeah, I agree that would be nice to have. Unfortunately with the spark-k8s-operator this is currently not possible - by any straight-forward or elegant means.

On the other hand, there have been recent discussions of a jupyter-operator coming up, which IMO would be a far better tool to have than just a shell.