Verifier: Added the option to set the correct and incorrect stats messages, providing the ability to set up impromptu 'yes/no' type polls/questions (think 'Did you find this article useful?  Yes or no.')

git-svn-id: https://plugins.svn.wordpress.org/my-optional-modules/trunk@798679 b8457f37-d9ea-0310-8a92-e5e31aec5664