EDU-1955: Adds header image and licence shield

Author: franrob-projects

README.md

@@ -1,3 +1,8 @@
+![Ably Pub/Sub Python Header](images/pythonSDK-github.png)
+
+![PyPI version](https://badge.fury.io/py/ably.svg)
+![License](https://img.shields.io/github/license/ably/ably-python)
+
 # Ably Pub/Sub Python SDK
 
 Build any realtime experience using Ably’s Pub/Sub Python SDK.