Fix issues with the changelog dialog

Sorry for those inconveniences I introduced. Fixed.

Before:
![image](https://cloud.githubusercontent.com/assets/2641501/2604852/9f3c56e4-bb3e-11e3-811c-95927dc3ef6e.png)
After:
![image](https://cloud.githubusercontent.com/assets/2641501/2604860/b367e426-bb3e-11e3-86dd-5cc6216dd05e.png)