Merge pull request #756 from mlimaloureiro/patch-1

Fix placeholder on contributing.

CONTRIBUTING.md

@@ -21,7 +21,7 @@ Please contribute links to packages/projects you have used or are familiar with.
 
 ## Quality standard
 
-To be on the list, project repositories should adhere to these quality standards (http://goreportcard.com/report/**github_user**/**github_user**):
+To be on the list, project repositories should adhere to these quality standards (http://goreportcard.com/report/**github_user**/**github_repo**):
 
 - Code functions as documented and expected
 - Generally useful to the wider community of Go programmers