new block: progressbar

![2014-12-02_1609](https://cloud.githubusercontent.com/assets/1333220/5263031/9ae9b42e-7a3d-11e4-9a1a-76abcf21cc69.png)

Also, what if I wanna to display percents inside the bar like bootstrap does http://getbootstrap.com/components/#progress-label ? It's impossible with this layout.