changed button padding inside large menu, fixes #1289

Before
![image](https://cloud.githubusercontent.com/assets/1714825/5261661/054a75f8-7a14-11e4-98de-421fb4fd2789.png)

After
![image](https://cloud.githubusercontent.com/assets/1714825/5261665/0b32aa8a-7a14-11e4-8e8b-b7737a6a7a74.png)