Cuetools.Converter.exe: support for --decoder-option parameter.

Implemented "Stream" option in BDLPCM Reader to make it possible to select
the right stream in m2ts file.

CUETools.Processor/CUESheetAudio.cs

@@ -11,6 +11,8 @@ namespace CUETools.Processor
         private long nextPos;
         private long _samplePos, _sampleLen;
 
+        public AudioDecoderSettings Settings { get { return null; } }
+
         public long Length
         {
             get { return _sampleLen; }