QML PingPong example added

Example presents the socket communication between two Bluetooth
devices. The basic concept is the ping pong game, where coordinate
updates of the ball and pedals are sent via socket.

Change-Id: I61d8eb0baaa11c1485a923bb0a6ae6b89cd0e6a9
Reviewed-by: Alex Blasche <alexander.blasche@digia.com>