Ported coffee charts to js


Signed-off-by: Sheik Hassan <solergiga@yahoo.com>
I don't think this will do what you expect it to do. The `for ... in` loop iterates over the enumerable properties of an object([more here](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Statements/for...in)) not the objects in a collection. Consider changing this to:

```javascript
for (var i = 0; i < this.collection.models.length; i++) {
    ...
}
```