Support scrollable text

Had issues when tried to make centre aligned text inside a div scrollable. Other option is to have a div inside a div but prefer not to have redundant elements on the page :)

What would happen is because the div didn't have any children the width will get calculated at 0 and the alignment would screw up...

For example:

```stylesheet
#banner {
width: 200px;
text-align:center;
margin: 0 auto;
}
#scrollable {
width: 50px;
white-space: nowrap;
text-align: center;
margin:0 auto;
}
```
```html
<div id="banner">
<div id="scrollable">I want to get scrolled properly even though I'm just simple text inside a simple div and the div doesn't have any children</div>
</div>
```
```javascript
$("#scrollable").smoothTouchScroll();
```
Merge pull request #3 from humancopy/patch-1

Support scrollable text