changed button padding inside large menu, fixes #1281

Before
![image](https://cloud.githubusercontent.com/assets/1714825/5261430/769be33e-7a11-11e4-987a-9e9b4687f4e4.png)

After
![image](https://cloud.githubusercontent.com/assets/1714825/5261436/894c460e-7a11-11e4-9d2f-d7ad9481c95d.png)