[SPARK-20196][PYTHON][SQL] update doc for catalog functions for all languages, add pyspark refreshByPath API

## What changes were proposed in this pull request?

Update doc to remove external for createTable, add refreshByPath in python

## How was this patch tested?

manual

Author: Felix Cheung <felixcheung_m@hotmail.com>

Closes #17512 from felixcheung/catalogdoc.