Calligraphy

#94 
- Use [calligraphy][0] for custom fonts (Roboto).
- Delete Typeface Views.
- Add [Roboto fonts 2.0][1].
- Update all layouts with the new font style - text appearance


[0]: https://github.com/chrisjenx/Calligraphy
[1]: http://www.google.com/design/spec/style/typography.html#typography-roboto