Display a list of posts that are similar or related to the current post.
Toolbelt can automatically append related posts to the end of post content. The related posts will be selected randomly from posts in the same categories as the post being viewed. A collection of posts are saved in a transient (specific to the current post), and then 2 posts are selected and appended to the end of the post content. Related posts with images are given priority, since they look nicer