Add Codacy badge

Author: nmatpt

README.md

@@ -2,6 +2,7 @@
 
 Ruby coverage reporter for Codacy https://www.codacy.com
 
+[![Codacy Badge](https://api.codacy.com/project/badge/72a7aaa0e3fd4a8db27607da159d3daa)](https://www.codacy.com/app/Codacy/ruby-codacy-coverage)
 [![Build Status](https://circleci.com/gh/codacy/ruby-codacy-coverage.png?style=shield&circle-token=:circle-token)](https://circleci.com/gh/codacy/ruby-codacy-coverage)
 
 Parses SimpleCov output and submits the result to Codacy