Merge pull request #536 from tylerdave/master

Fixed broken contributing link

Author: sigmavirus24

CONTRIBUTING.md

@@ -4,7 +4,7 @@ How to contribute
 This guide is under heavy development. If you would like to contribute, please
 see:
 
-http://docs.python-guide.org/en/latest/notes/contribute.html
+http://docs.python-guide.org/en/latest/notes/contribute/
 
 
 Style Guide