Module Related Posts: Bring dashboard settings preview more inline with what is generated by the module.
Module Related Posts: Add shortcode to allow for custom placement within content.

Add a optional shortcode `[jetpack-related-posts]` which users can place
anywhere in the post content to display a related post section. If no
shortcode exists we default back to placing it at the bottom of the post as
happens now.
Merge pull request #319 from xyu/related-post-shortcode

Module Related Posts: Add a shortcode for custom placement