Add black badge (#107)

Mariatta · web-flow · commit de5e57812a63 · 2018-06-15T19:28:56.000-07:00
diff --git a/README.rst b/README.rst
@@ -1,6 +1,9 @@
 miss-islington
 ==============
 
+.. image:: https://img.shields.io/badge/code%20style-black-000000.svg
+    :target: https://github.com/ambv/black
+
 🐍🍒⛏🤖
 
 Bot for backporting `CPython <https://github.com/python/cpython/>`_ Pull Requests.
