Devoncarew more polymer

Change the `spark-icon-button`s in the toolbar to `spark-button`s. IMHO this improves their look and feel.

![screen shot 2014-01-13 at 7 34 32 am](https://f.cloud.github.com/assets/1269969/1901696/519e0b18-7c68-11e3-90b7-2d503be099e8.png)

@ussuri