[SPARK-13792][SQL] Addendum: Fix Python API

## What changes were proposed in this pull request?
This is a follow-up to https://github.com/apache/spark/pull/13795 to properly set CSV options in Python API. As part of this, I also make the Python option setting for both CSV and JSON more robust against positional errors.

## How was this patch tested?
N/A

Author: Reynold Xin <rxin@databricks.com>

Closes #13800 from rxin/SPARK-13792-2.