Updating MR area to be workflow-based

This MR moves pages in this section so the area is workflow-based. Users should start to understand how to use the feature because of the way the pages flow from top to bottom. So you want to start with create, then add bells and whistles. I tried to start with possible workflows, then create, then options while you're creating, then how to merge, and what to do after merge. Finally, things that are optional offshoots.