Redirect to original link after logging in when visiting a DU app link while not logged in

[lilliealbert]

Right now if I send someone a link to the app and they aren't logged in, they just redirected to the home page and their original destination is lost. I'd like users to be prompted to log in when they try to hit a page they don't have access to, instead of silently being redirected.

[brittag]

I believe this is important to do before we welcome new membership applications, because in my experience as a former membership coordinator, a bunch of new members got confused by it and needed my help. They would click a link in an automated DU email (such as to set up their dues), log in, and then have trouble finding the dues page again. So we can reduce burden on the membership coordinator by fixing this!