auth.auth relies on the client passing in their user id and api key to authenticate. This is great for ajax calls, but won't work when we need to download files, so we need a way for the router to authenticate via the current session. That is all dataexport.auth does. As I mentioned above, there is probably a more elegant way of doing that, but I couldn't immediately figure it out. I'm guessing something to do with `passport` and loading the current session, but no such function exists for the express router. Perhaps one should be added to the auth controller.