app.post('/users', function(req, res){
  username = req.body.username;
  password = req.body.password;
  password_confirm = req.body.password_confirm;
  email = req.body.email;
  if (password === password_confirm){
    parse = new Parse(APP_ID, MASTER_KEY);
    parse.insertCustom('users', {"username": username, "password": password, "email": email}, function (err, resp) {
    parse.getUser(username, password, function(errr, respo){
      if (respo){
        req.session.user = respo;
        res.render("index");
     } else {
        res.render('signin');
      }
    })
  });
 } else {
  res.render("signin");
 }
});