refs #9192
- Moving towards a centralised concept of routing / routes
- The base router now wraps express router, and offers us the features we need
- Site Router is the parent router, it gets initialised with all of our default routing
- App Router is a sub router for apps - apps register their routes/routers onto it.
- TODO: refactor channels subrouter to work this same way
- MAYBE: move the app router to the apps service
refs #9192
- Admin redirects should really happen first, up with custom redirects
- Later we can package this up, maybe
- For now, let's focus the site router on site-related things
