title: Passport LocaStrategy signup redirect issue
body: <p>I am trying to redirect user after signup on Passport</p>
  
  <pre><code>passport.use('local-signup', new LocalStrategy({
  usernameField : 'username',
  passwordField : 'password',
  passReqToCallback : true},
  function(req, username, password, done) {
  
      // asynchronous
      // User.findOne wont fire unless data is sent back
      process.nextTick(function() {
  
      // find a user whose username is the same as the forms username
      User.findOne({ username :  username }, function(err, user) {
          // if there are any errors, return the error
          if (err)
              return done(err);
          if (user) {
              return done(null, false, req.flash('signupMessage', 'Username is already taken.'));
          } else {
              var newUser = new User();
              newUser.username = username;
              newUser.password = password;
              newUser.email = req.body.email;
              newUser.save(function(err) { // create user
                  if (err) {
                      return next(err);
                  } else {
                      var site = new Site({user : newUser.username, siteTitle: newUser.username});
                      site.save(function(err) { // create website
                          if (err) {
                              return next(err);
                          } else {
                          newUser.sites.push(site); // push site'id in sites field in user
                          newUser.save(); // save user after site'id has been push
                          };
                      });
                  };
              res.redirect('users/' + username);
              });
              ...
  </code></pre>
  
  <p>and I get <strong>ReferenceError: res is not defined</strong></p>
  
  <p>Any help would be appreciated as I am starting Mean dev.</p>
  
  <p>Thanks a lot</p>