Increase threshold in xxxDiff() functions to detect lighter/darker colors

Signed-off-by: Jacky Boen <aqiank@gmail.com>
Added some comments

Signed-off-by: Jacky Boen <aqiank@gmail.com>
Changed gradient outer color to be the same as the inner color.

Signed-off-by: Jacky Boen <aqiank@gmail.com>
Updated sound filenames

Signed-off-by: Jacky Boen <aqiank@gmail.com>
Added minimum volume so we can hear something even if the objects are too small

Signed-off-by: Jacky Boen <aqiank@gmail.com>