SpeedLimit 0.2

And here is the second version of speedlimit.

Changelog:
- audio alarm when you go faster than limit
- now gps speed updates every 0.5 seconds
- Label with the selected speedlimit
- two buttons to increase/decrease speedlimit in 5 km/h
- initial work to support non-tablet (netbooks, etc)
- many GUI improvements
- many bug fixes

TODO:
- Support miles per hour
- Configurable buttons (for different speeds)
- Make it more beautiful (bigger font, and more)