Hg wrap inlines

This change the functionality to wrap inline elements that can be wrapped. The list is not conclusive at the moment but ti's easy to add to them. Wrapping inline elements means we can merge them with non-inline etc. and will make extending off the end of the node much simpler
Off the top of my head, you can add OL, H1-6. Can you check if there is not already a helper for that in scribe-common? There're variants of this heuristic *everywhere* :-(