Remove related container if empty

### Before

![screen shot 2014-12-02 at 14 11 49](https://cloud.githubusercontent.com/assets/74132/5263829/66100db2-7a2d-11e4-9da2-5bdfd683ec98.png)

### After

![screen shot 2014-12-02 at 14 11 44](https://cloud.githubusercontent.com/assets/74132/5263832/69491578-7a2d-11e4-9de8-513017589a62.png)