Grunt + Bower support

Ladda for Bootstrap is great! Too bad it doesn't build with Grunt and deliver with Bower. So, here's a pull request to support both Grunt and Bower!
Compile with:
````
$ npm install
$ grunt
````
And use it in any project with Bower, putting in your `bower.json`:
````json
{
    "dependencies": {
        "ladda-bootstrap": "~0.8.0"
    }
}
````