removed outline from modal

Chrome shows an outline for modal. It does not seem to be intended (or is it?) and looks a bit strange when the scrollbar is inside the outlined container.

![modal-jsfiddle](https://f.cloud.github.com/assets/3200800/1274558/0d05c378-2db3-11e3-8f65-d1ce16fa53bd.jpg)

You can compare the two jsFiddles here:
http://jsfiddle.net/QA2He/ -- with outline
http://jsfiddle.net/8KXsc/1/ -- without outline