mnit_android: Adding SensorEvent in input_event module

Signed-off-by: Romain Chanoir <chanoir.romain@courrier.uqam.ca>
mnit_android: Adding android_sensor module

Signed-off-by: Romain Chanoir <chanoir.romain@courrier.uqam.ca>
mnit_android: changes android_app to support android_sensor

Signed-off-by: Romain Chanoir <chanoir.romain@courrier.uqam.ca>
examples: Adding mnit_ballz, a game using android_sensor API

Signed-off-by: Romain Chanoir <chanoir.romain@courrier.uqam.ca>
Merge: Android Sensors + mnit_ballz

Adding support for the basics android sensors:
accelerometer, magnetic field, gyroscope, light and proximity

and add mnit_ballz, an app testing theses sensors

Pull-Request: #359
Reviewed-by: Jean Privat <jean@pryen.org>
Reviewed-by: Alexis Laferrière <alexis.laf@xymus.net>
Reviewed-by: Alexandre Terrasa <alexandre@moz-code.org>