title: Get route definition in middleware
body: <p>Does anyone know if it's possible to get the path used to trigger the route?</p>
  
  <p>For example, let's say I have this:</p>
  
  <pre><code>app.get('/user/:id', function(req, res) {});
  </code></pre>
  
  <p>With the following simple middleware being used</p>
  
  <pre><code>function(req, res, next) {
       req.?
  });
  </code></pre>
  
  <p>I'd want to be able to get <code>/user/:id</code> within the middleware, this is not <code>req.url</code>.</p>