Added test for issuing get request on ne article as user not signed in.
Refactored articles controller to use a before filter like all the other controllers in his class do.
Merge branch 'master' into paper-trail
Added routes for versions of articles.
Implemented link from articles page to different versions of the article.
Added view for listing versions of an article and corresponding links and controller action.
Removed every trace of the old versioning idea.