Implemented lap time/race time.
Lap time/race time is stored in Racer in Racer:AdvanceLap and Racer:Finish. The values are currently unused.
Refactored cRace.lua, made network event subscribing cleaner.
"Time limit up, ending race" is broadcast to the race now, instead of the server.
Added a debug message in Race:NetworkSendRace.