Updated spectral display to used dBm scale and removed baseline/amplification items.

Updated sample handling code to use -1.0 to 1.0 float values throughout, to support P25 decoder and symbol filter.

src/source/tuner/rtl/RTL2832TunerController.java

@@ -52,6 +52,7 @@ import org.usb4java.Transfer;
 import org.usb4java.TransferCallback;
 
 import sample.Listener;
+import sample.adapter.ByteSampleAdapter;
 import sample.complex.ComplexBuffer;
 import source.SourceException;
 import source.tuner.FrequencyChangeEvent;