CONTRIBUTING.md in berkshelf-3.0.0.beta1 vs CONTRIBUTING.md in berkshelf-3.0.0.beta2

- old
+ new

@@ -15,9 +15,11 @@
 
 ## Testing
 
 ### Install prerequisites
 
+Install git and mercurial on your test system. (http://mercurial.selenic.com/wiki/Download)
+
 Install the latest version of [Bundler](http://gembundler.com)
 
     $ gem install bundler
 
 Clone the project