This is the last batch of changes to complete SPARK-7929.

Previous related PRs:
https://github.com/apache/spark/pull/6480
https://github.com/apache/spark/pull/6478
https://github.com/apache/spark/pull/6477
https://github.com/apache/spark/pull/6476
https://github.com/apache/spark/pull/6475
https://github.com/apache/spark/pull/6474
https://github.com/apache/spark/pull/6473

Author: Reynold Xin <rxin@databricks.com>

Closes #6487 from rxin/whitespace-lint and squashes the following commits:

b33d43d [Reynold Xin] [SPARK-7929] Turn whitespace checker on for more token types.