adds some padding below the title

Currently the title and the meta information are somewhat attached to each other.
See http://haacked.com/archive/2013/12/03/jekyll-url-extensions/

**Before**
![haacked_before](https://f.cloud.github.com/assets/542458/1671626/7e3af6d6-5cbf-11e3-9b77-cb6827b7d0df.png)

**After**
![haacked_after](https://f.cloud.github.com/assets/542458/1671627/82b77d2e-5cbf-11e3-9c40-5cbfa1a0fd29.png)