Redirect user if they are logged in and land on homepage

- redirect authenticated users to landing page
Redirect user if they are logged in and land on homepage

- load the landing page at the root
- redirect to the login page if they are not authenticated
Merge pull request #441 from strongloop/feature/logged-in-redirect

Redirect user if they are logged in and land on homepage

- load the landing page at the root
- redirect to the login page if they are not authenticated

Fix #433