[ci skip] Fix 4.2 release notes rendered display.

## Before

![screenshot 2014-07-09 15 09 03](https://cloud.githubusercontent.com/assets/1000669/3520906/9c999cd0-0738-11e4-8a25-44bbcea46c4a.png)

![screenshot 2014-07-09 15 09 13](https://cloud.githubusercontent.com/assets/1000669/3520907/9ca05dc2-0738-11e4-825a-0d5b2ead5080.png)

![screenshot 2014-07-09 15 09 21](https://cloud.githubusercontent.com/assets/1000669/3520903/9c87cc8a-0738-11e4-926e-4bbe9d770f94.png)

## After

![screenshot 2014-07-09 15 11 57](https://cloud.githubusercontent.com/assets/1000669/3520904/9c889e4e-0738-11e4-9941-bb20da38ce9d.png)

![screenshot 2014-07-09 15 12 02](https://cloud.githubusercontent.com/assets/1000669/3520905/9c89deda-0738-11e4-8ed8-5a7d60484c2c.png)

![screenshot 2014-07-09 15 12 13](https://cloud.githubusercontent.com/assets/1000669/3520902/9c86f0b2-0738-11e4-999a-918ad08cc7f4.png)