- Added support for custom data in the MediaInfo object class + other fix

[GoMino]

• Make sure the ConnectableDevice id is set with the serviceDescription UUID if any, instead of a generated one.
• Fix the ConnectableDevice constructor with a JSONObject as argument to properly initialize the serialized DeviceServices if any.
• Fix a bug where the serviceDescription does not get set to the ConnectableDevice when first discovered (was only set on the DeviceService at first, and then on the ConnectableDevice, when it get updated).
• Added Support for startPosition and customData parameters in playMedia method of MediaPlayer capability.