added pipy badge to README

README.md

@@ -7,6 +7,7 @@
 [![codecov](https://codecov.io/gh/freude/NanoNet/branch/master/graph/badge.svg)](https://codecov.io/gh/freude/NanoNet)
 [![CodeFactor](https://www.codefactor.io/repository/github/freude/nanonet/badge/master)](https://www.codefactor.io/repository/github/freude/nanonet/overview/master)
 [![Codacy Badge](https://api.codacy.com/project/badge/Grade/5186e15b951d4df6b4f20c2365870b7c)](https://app.codacy.com/app/freude/NanoNet?utm_source=github.com&utm_medium=referral&utm_content=freude/NanoNet&utm_campaign=Badge_Grade_Dashboard)
+[![PyPI version](https://badge.fury.io/py/nano-net.svg)](https://badge.fury.io/py/nano-net)
 
 <img src="https://user-images.githubusercontent.com/4588093/65398380-1f684380-ddfa-11e9-9e87-5aab6cf417b8.png" width="200">