leverage hardware button to free from Mac's keyboard

[HBehrens]

The hardware button of the Camera could be used to

• bring to / dismiss from foreground & full screen (single push)
• rotate the picture clockwise (double push) and ccw (tripple push)

The buttons seems to be accessible as USB HID. This link might help
https://developer.apple.com/library/mac/#samplecode/HID_Utilities_Source/Introduction/Intro.html