Work in progress, limiting AudioFeedback options in XML to LONG_CLICK, SEQUENTIAL

Signed-off-by: Michalis Vitos <info@michalisvitos.gr>
Limit AudioFeedback options in XML to LONG_CLICK, SEQUENTIAL

Signed-off-by: Michalis Vitos <info@michalisvitos.gr>
Changed XML attribute name from choiceAudio to answerDesc

Signed-off-by: Michalis Vitos <info@michalisvitos.gr>
Added questionDesc attribute in XML

Signed-off-by: Michalis Vitos <info@michalisvitos.gr>
Create AudioFeedbackController class to manage AudioFeedback functionality

Signed-off-by: Michalis Vitos <info@michalisvitos.gr>
Allowing the volume buttons to increase decrease the volume. The minimum volume can be decreased only up to half of the max volume.

Signed-off-by: Michalis Vitos <info@michalisvitos.gr>