Updated nav drawer visual style, simplified settings activity, better saving of state across configuration changes

The title says it all.

Here is a screenshot of the updated nav drawer style.
![screenshot_2014-05-07-21-45-01 1](https://cloud.githubusercontent.com/assets/1476544/2911408/0cc5053a-d65b-11e3-8621-63792a3d3ca6.png)