Icons in the navigation drawer and some small changes

Changes made:
- Icons for items in navigation drawer. (All icons except the ones for Most Popular and My List are from Action Bar Icon Pack. The other 2 icons were made by me.)
- Increase font size of navigation drawer item titles.
- Add 5dp bottom padding to user name in profile activity.
- Added Thumbs.db to gitignore file.

Screenshot:
![device-2014-02-24-171527](https://f.cloud.github.com/assets/2550945/2247443/e2ad2194-9d6e-11e3-8ef5-ac62d509300c.png)