Updates pull request from Roman Tsypuk to convert the build system from

ant to gradle.  Removes linux and windows application launch scripts and
produces an executable jar with all resources included.

src/main/java/io/github/dsheirer/dsp/gain/ComplexGain.java

@@ -0,0 +1,31 @@
+package io.github.dsheirer.dsp.gain;
+
+import io.github.dsheirer.sample.Listener;
+import io.github.dsheirer.sample.complex.Complex;
+
+public class ComplexGain implements Listener<Complex>
+{
+	private float mGain;
+	private Listener<Complex> mListener;
+
+	public ComplexGain( float gain )
+	{
+		mGain = gain;
+	}
+	
+	@Override
+	public void receive( Complex sample )
+	{
+		if( mListener != null )
+		{
+			sample.multiply( mGain );
+			
+			mListener.receive( sample );
+		}
+	}
+
+	public void setListener( Listener<Complex> listener )
+	{
+		mListener = listener;
+	}
+}