Power up sound, viewcontrollers, and short feature

Add sound effects when choosing a language, tap a battery/switch, win/lose the level
Abandon storyboard, and segue different viewcontrollers programmatically
   Menuviewcontroller will pass language to levelviewcontroller
   Levelviewcontroller will pass language and total levels to gameviewcontroller
   gameviewcontroller will pass back language to levelviewcontroller (so language is consistent all the time)
Implement short features (change the image of the bulb and update the alertview message)
   If the circuit is shorted, the alertview will ask the user to restart the current level
Add a test file (level4) for short features

TODO:
more sound effects
when levelviewcontroller pass the language back to menuviewcontroller, segmented control fails to work, and buttons on menuviewcontroller have titles on top of another