RactiveJS/Ractive-adaptors-Backbone — pull request #3 by bartsqueezy (2013-12-22 00:24:08+00:00)
Title: if property in template data is a model, setting it to null will break reset method

Let's say I have a Ractive view of

```javascript
var view = new Ractive.extend({
template: template,
data: {
content: new Backbone.Model.extend()
}
});
```

If later in my application I decide to execute `view.set('content', null)`, this will cause an error in the reset method of the `BackboneModelWrapper`. Since `null` is described as an `Object` in JavaScript, the current `typeof` check will fail. This PR updates the `typeof` check to use `instanceof` for better type checking accuracy.