Address `overflow` in `button` set to `hidden` in IE 8/9/10.

So, basically, IE defaults to `overflow: hidden` in `button` elements. I met this issue when I was trying to add an `:after` pseudoblock to `button`.

I've made a little [test page](http://dizaina.net/browser_test/button) to test this out. [Here's the result](http://dizaina.net/browser_test/button_overflow.jpg).

As you can see, `overflow: visible` addresses the issue for absolutely positioned blocks and almost adresses it for static blocks (chrome's acting weirdly).