Updated on Aug 5, 2016
Version 1 code 3:
Fix Bugs:
1,restore sound state when resume game.
2,stop engine sound when game over and game pause.
Add Features:
1,add sound control button in pause panel.
2,can eat gas to get protection and speed up.
3,remove ad when mile < 2000.
Version 1 code 2:
1,Remove AD when game pause.
2,Edit rate function
