Create README.md

Author: machow

README.md

@@ -4,7 +4,9 @@ sqlwhat-ext
 [![Build Status](https://travis-ci.org/datacamp/sqlwhat-ext.svg?branch=master)](https://travis-ci.org/datacamp/sqlwhat-ext)
 [![PyPI version](https://badge.fury.io/py/sqlwhat-ext.svg)](https://badge.fury.io/py/sqlwhat-ext)
 
-extensions (high-level SCTs) for sqlwhat.
+Extensions (high-level SCTs) for sqlwhat. 
+
+[Documentation here](http://sqlwhat-ext.readthedocs.io/).
 
 Including in a DataCamp course
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