'before' method is undefined on expressjs

I am using `kontroller` with an expressapp. Here is the [controller](https://github.com/ktkaushik/kontroller_sample/blob/master/controllers/posts_controller.js) i created named as `posts_controller.js`

In here, i keep getting an error saying that `before` is undefined.

```
before(think, {only: 'accelerate'});
^
TypeError: Property 'before' of object function Controller() {
if (!(this instanceof Controller)) {
return BaseController.route(arguments[0]);
}

BaseController.call(this);
} is not a function
at Object. (/Users/kaushik/dev/my_repos/kontroller_sample/controllers/posts_controller.js:4:8)
at Module._compile (module.js:449:26)
at Object.Module._extensions..js (module.js:467:10)
at Module.load (module.js:356:32)
at Function.Module._load (module.js:312:12)
at Module.require (module.js:362:17)
at require (module.js:378:17)
at Object. (/Users/kaushik/dev/my_repos/kontroller_sample/app.js:11:13)
at Module._compile (module.js:449:26)
at Object.Module._extensions..js (module.js:467:10)

```