title: Node.js req.user won't be global in res.locals.user
body: <p>I try to put my <code>req.user</code> value in the global variable for all views with </p>
  
  <pre><code>app.use(function(req, res, next){
      res.locals.user = req.user; // this line
      res.locals.success = req.flash('success');
      res.locals.error = req.flash('error');
      next();
  });
  </code></pre>
  
  <p>but nothing works. I have to put it on every <code>render()</code> function. What did I do wrong?</p>
  
  <p>Thank you for your help!</p>