Decouples DecoderState from the Decoder and makes DecoderState inherit

from Module so that Decoder can function independent of DecoderSTate and
DecoderState can more cleanly interface with other modules. 

Resolves issue with LTR-type decoders where the AudioModule was
filtering demodulated audio buffers before the decoder received the
audio - demodulated audio buffers are now copied before creating
AudioPackets.

src/module/decode/state/DecoderStateEvent.java

@@ -21,6 +21,18 @@ public class DecoderStateEvent
 		mFrequency = frequency;
 	}
 	
+	public String toString()
+	{
+		StringBuilder sb = new StringBuilder();
+		
+		sb.append( "Decoder State Event - source[" + mSource.getClass() + 
+				"] event[" + mEvent.toString() + 
+				"] state[" + mState.toString() +
+				"] frequency [" + mFrequency + "]" );
+		
+		return sb.toString();
+	}
+	
 	public Object getSource()
 	{
 		return mSource;