Import bug fixes for camera and video files.
Mute button added, still need fixing.
Mute functions added, try KeyListener. No camera problems.
Piano button added to remove and add piano view from SheetMusicActivity.
Mute button still need some fixing.
Merge LandscapeView, Piano and Mute Buttons, Metronome, Video Files
Path, + and - Buttons, Metronome, and OnKeyListener (doesn't work)
Merge remote-tracking branch 'origin/master'