title: Use res.send and res.json together
body: <p>I want to create a file <code>config.js</code> containing JSON code.
  Here is my code on app.js</p>
  
  <pre><code>app.get('/config.js', function(req, res) {
    var JSON = {
      "info": {
          "level1":  "Jeopardy Ready",
          "level2":  "Jeopardy Contender",
          "level3":  "Jeopardy Amateur",
          "level4":  "Jeopardy Newb",
          "level5":  "Stay in school, kid..." // no comma here
      }
    };
    res.format({'text/plain': function(){
      res.send(" var JSON = ");
    }
    });
   res.json(JSON);
  
  });
  </code></pre>
  
  <p>I want to have result in config.js</p>
  
  <pre><code>var JSON = {
      "info": {
          "level1":  "Jeopardy Ready",
          "level2":  "Jeopardy Contender",
          "level3":  "Jeopardy Amateur",
          "level4":  "Jeopardy Newb",
          "level5":  "Stay in school, kid..." // no comma here
      }
      ]
    };
  </code></pre>
  
  <p>Any idea how to make it?
  In my code I tried to use res.send and res.json together, but it couldn't works.</p>