Add jquery dependency

The jquery dependency is missing:

```
Running "connect:server" (connect) task
Started connect web server on http://localhost:8888

Running "handlebars:build/templates.js" (handlebars) task
File build/templates.js created.

Running "browserify:build/boundle.js" (browserify) task
>> Error: module "jquery" not found from "node_modules/backbone/backbone.js"
```