TODO: move auth check into root-config

[filoxo]

For this example, I think the auth check should be moved into root-config as part of the application's activityFn. That way the applications don't even load if you're not authenticated. Its not bad per se (all of the assets are public anyway!) but seems a little "more correct" as well as having a slight perf benefit. (or is it? Since an unauthenticated user will need to download the home app anyway after logging in...) In any case, that would mean replacing the single-spa-layout definitions with registerApplications because single-spa-layout routes are currently limited to only using a path and nothing more.

[filoxo]

I implemented this on check-auth-in-root-config as a separate branch and have made note of it in the README.