Main Page/feature/doc

This is the featured article that appears on the Main Page.

When changing this feature:
 * Ensure you only pick the best pages
 * Pick a good extract from the article that works well on its own
 * Ensure you have lots of links in the extract
 * Include  at the bottom, to link to the full article
 * Include  at the bottom, to ensure this help text shows up on the page