fix coverage badge in README.md

Author: PascalSchumacher

README.md

@@ -44,7 +44,7 @@ Apache Commons IO
 ===================
 
 [![Build Status](https://travis-ci.org/apache/commons-io.svg?branch=master)](https://travis-ci.org/apache/commons-io)
-[![Coverage Status](https://coveralls.io/repos/apache/commons-io/badge.svg?branch=master)](https://coveralls.io/r/apache/commons-io)
+[![Coverage Status](https://coveralls.io/repos/github/apache/commons-io/badge.svg?branch=master)](https://coveralls.io/github/apache/commons-io?branch=master)
 [![License](http://img.shields.io/:license-apache-blue.svg)](http://www.apache.org/licenses/LICENSE-2.0.html)
 
 The Apache Commons IO library contains utility classes, stream implementations, file filters,