Merge pull request #1 from cg50x/master

Playback with SoundPool
Merge pull request #2 from cg50x/master

Release SoundPool upon exiting PlayState
Refactored click event to touch event
Implemented Ads and switch height

Implemented Ads - requires you to reference google-play-services_lib as
separate library project. See
http://developer.android.com/google/play-services/setup.html

Fixed multiple startRecording bug.