Fix modelFor('application') in dummy app's nodes route

[samchrisinger]

The nodes route is trying to fetch the current user (loaded in the application route's model hook-- this.modelFor('application')). Unfortunately the application route's model hook is only run once (when the SPA is first loaded) and there is a slight timing issue between the dummy app's login route (which parses the OAuth token from the query string and "logs in" the user) and when the application route runs. Basically on redirect from the OSF CAS:

ApplicationRoute.model returns null -> LoginRoute parses token and authenticates user -> redirected to index page -> you click "My Nodes", but the ApplicationRoute's model is still null

So when you refresh the page or visit the nodes page directly, the ApplicationRoute is able to correctly fetch the current user.

[samchrisinger]

Fixed in db2e847