UI Tweaks for History Viewer II

Actual view
![captura de tela 2014-04-15 as 03 05 56](https://cloud.githubusercontent.com/assets/1726914/2704113/e7ae1a2c-c465-11e3-8f22-241f587a8d0c.png)

After tweaks
![captura de tela 2014-04-15 as 03 16 19](https://cloud.githubusercontent.com/assets/1726914/2704115/f1133624-c465-11e3-846c-3efae62ac457.png)
![captura de tela 2014-04-15 as 03 16 37](https://cloud.githubusercontent.com/assets/1726914/2704116/f2bf215e-c465-11e3-9db9-82eb99d51521.png)