1. Add lightning effect (animation and sound) when clearing 2 or more lines in one drop in a double fight game.
2. If a double game can not be initilized well, a toast message will be displayed to remind the player.
Fix:
1. On some devices, pressing power in playing game and returning to the game in some minutes will cause the game go into the abnormal state. (ex: play game with "N/A" / crash)
2. On some devices, changing to another app and returning to the game in some minutes will cause the game go into the abnormal state. (ex: black screen / crash)