Routable middleware

Added option to have routed middleware by using an array. The 1st
argument is the route, the second is the handler.

```js
connect: {
  options: {
    middlware: [
      ['/routable-middleware', function (req, res) {
        res.end('I\'ll only run on "/routable-middleware"');
      }]
    ]
  }
}
```