Finish server side driving logic

- Fix lane allocation - was busy looping
- Make matrix configuration more sane, allowing validation of message
  values (e.g. action in oonfig.ACTIONS).
- Cleanup matrix drawing
- Using currently simple if/else block for dipatching actions, since
  the table did not work as it was defined. This may be simplified later
  using a table.

Client driving logic is not there yet - we need to initialize all cars
on init, allocate a car to each player by player name, and draw the car
according to the player lane and speed.