ccc1.61版本中，更新svn过程中，场景的uuid会丢失，按照官方的教程处理也是一样，求解决。
The Asset used by component “cc.Sprite” in scene “Main.fire” is missing. Detailed information:
Node path: “Canvas/MainBg/MainUI/DownUI/TouziBox/TouziBtn”
Asset url: “db://assets/Scene/Main.fire”
Missing uuid: “20deacc3-a8ab-474a-9b8a-73bfbba5ff6d”