Calculates ranking_points, based on newness and upvotes.
Recreated fixtures/initial_data.json.
Upvote works, returns to current page or home page depending on HTTP_REFERER.
Submitting automatically upvotes; can't resubmit same article.
Upvote buttons hidden for non-logged-in users.
Merge pull request #5 from ehmatthes/new_page

New page