Styled Bulter widget (inspired by Alfred's awesome white theme)

CSS styles added. 

.butler-ui-widget class added to butler widget so that styles are
namespaced to the butler widget only (and not any other use of jQuery UI dialog widget). 

![Screen Shot 2013-01-27 at 11 56 04 am](https://f.cloud.github.com/assets/611704/100495/5d1a9120-681c-11e2-9c6d-8f53b306d318.png)