[IPlayer] Add struct IPlayerAudioStreamInfo and GetAudioStreamInfo(int iStream, IPlayerAudioStreamInfo &info).
[Players/GUIInfo/JSON] Remove GetAudioBitrate() and move its functionality to GetAudioStreamInfo(int index, IPlayerStreamInfo &info)
[Players/LegacyPlayer/JSON] Remove GetAudioStreamLanguage(int iStream, CStdString &strLanguage) and move its functionality into GetAudioStreamInfo(int index, IPlayerStreamInfo &info)
[Players/GUIInfo/JSON] Remove GetChannels() and move its functionality into GetAudioStreamInfo(int index, IPlayerStreamInfo &info)
[Players/GUIInfo/JSON] Remove GetAudioCodecName() and move its functionality into GetAudioStreamInfo(int index, IPlayerStreamInfo &info)
[Players/GUI/LegacyPlayer/JSON] Remove GetAudioStreamName(int iStream, CStdString &strStreamName) and move its functionality into GetAudioStreamInfo(int index, IPlayerStreamInfo &info)