Local auth example improvements

[marr]

This change is to improve the Local Auth example by supporting redirecting back to the place you were at before being logged out in a server page load context. In other words, you could be on /secret, and delete your cookies. When you try to login via hard load of /secret, the login page will be aware of where you previously were, and correctly bring you back to /secret.

This may require some more work, as you do see the 'protected' page for an instant during the redirect.