Enhanced the res.end('Unauthorized') response

I have found that when using Passport within an app does not handle errors, like an API, I have little way to communicate helpful error messages to the endpoint request. This would make the 401 - Unauthorized response a bit more robust.

Example for Local Strategy:

passport.use("local", new LocalStrategy(function(username, password, done) {

    store.findUserByUsername(username, function(err, user) {
      if (err) 
        return done(null, false, { name: 'Error', message: err.message } );

      if (!user) {
        return done(null, false, { name: 'NoAccountFound', message: 'Invalid Username and Password.' } );
      } else {
        done(null, user);
      }

    });
  }
));

Returning:

401 

[
  {
    "name": "NoAccountFound",
    "message": "Invalid Username and Password."
  }
]