Add information to navigation for active routes
Add information to navigation for active routes

The `current-when` property on <LinkTo> lets us provide a space
separated list of all the routes that are logically part of each
section. This ensures that the navigation remains 'current' and selected
even when we're in the sub sections.

ilios/frontend,dartajax/frontend,dartajax/frontend,ilios/frontend,jrjohnson/frontend,jrjohnson/frontend