Viral posts

DEV NOTE: Viral is the algorithm page, customized by users

Every few minutes, we'll loop through most-recent, and select popular posts to be viral. It is a sliding scale, and we'll play with the thresholds. Then, based on a user's content settings, we'll show barely/heavily-viral posts.

Every hour or so, we'll loop through viral posts, select the most popular ones, and those will go onto the homepage.