Tweaks to <h2> header text

....since it was getting truncated by the "collapsible" functionality.

Before:
<img src="https://cloud.githubusercontent.com/assets/6394533/3259045/dc3db0dc-f23f-11e3-9060-b078fa67eae9.png" width="300">

After:
<img src="https://cloud.githubusercontent.com/assets/6394533/3259046/dc67fd56-f23f-11e3-842a-e2f58a6d27ff.png" width="300">