Reduces size of message header font

Before:
![screen shot 2014-11-25 at 2 51 12 pm](https://cloud.githubusercontent.com/assets/186715/5193120/906f2f96-74b2-11e4-8944-6494c557ee21.png)

After:
![screen shot 2014-11-26 at 4 57 52 pm](https://cloud.githubusercontent.com/assets/186715/5211029/71e7cf98-758d-11e4-8bf9-cfa174a4da3f.png)