Add pypi badge

Author: manics

README.md

@@ -2,6 +2,7 @@ Jupyter Offline Notebook
 ========================
 
 [![Binder](https://mybinder.org/badge_logo.svg)](https://mybinder.org/v2/gh/manics/jupyter-offlinenotebook/master?filepath=example.ipynb)
+[![PyPI](https://img.shields.io/pypi/v/jupyter-offlinenotebook.svg)](https://pypi.python.org/pypi/jupyter-offlinenotebook)
 
 Save and load notebooks to browser storage, even if you've lost your connection to the server.