Remove cursor: pointer from the header

Hello!

The new website is looking super smart, great work. :dancer: 

I noticed the header has cursor: pointer on it which makes the entire navigation highlight when interacting with it on Chrome for Android.

![screenshot_2014-11-11-19-30-12](https://cloud.githubusercontent.com/assets/2445413/4999416/12f7e5d6-69da-11e4-9eab-afb299b19a46.png)