Studio: Course Outline Static Rendering/Styling

This work provides some rendering support of the bulk publishing-related course outline changes.
Using ```list-sections``` here is a little tricky for me. I don't know what the potential children are, I don't want to enforce a hierarchy, and even if I did I don't know how to pluralize the name! I could hack this for the key classes, but what will happen if we get a split_test included? I won't know whether the children are subsections, units or some kind of components.