Reviewed Additional Javascript Tests

@clarkbarz reviewed the javascript tests in pull request #128, which was requested in #127. 
How about I just delete this one? destroy is an jqXHR request and closeAll is tested by you here: https://github.com/fusionbox/django-widgy/blob/fd631f2dc56be0cff003028c4bf81a9c1857044d/js_tests/tests/test_widgy.backbone.js#L61. I also don't like the setup either.