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/am/AMDemodulator.java

@@ -0,0 +1,22 @@
+package io.github.dsheirer.dsp.am;
+
+public abstract class AMDemodulator
+{
+	private float mGain;
+	
+	public AMDemodulator( float gain )
+	{
+		mGain = gain;
+	}
+	
+    public float demodulate( float inphase, float quadrature )
+    {
+    	return (float)Math.sqrt( ( inphase * inphase ) + 
+    							 ( quadrature * quadrature ) ) * mGain; 
+    }
+    
+	public void setGain( float gain )
+	{
+		mGain = gain;
+	}
+}

src/main/java/io/github/dsheirer/dsp/am/AMDemodulator_CB.java

@@ -0,0 +1,69 @@
+/*******************************************************************************
+ *     SDR Trunk 
+ *     Copyright (C) 2014,2015 Dennis Sheirer
+ * 
+ *     This program is free software: you can redistribute it and/or modify
+ *     it under the terms of the GNU General Public License as published by
+ *     the Free Software Foundation, either version 3 of the License, or
+ *     (at your option) any later version.
+ * 
+ *     This program is distributed in the hope that it will be useful,
+ *     but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *     GNU General Public License for more details.
+ * 
+ *     You should have received a copy of the GNU General Public License
+ *     along with this program.  If not, see <http://www.gnu.org/licenses/>
+ ******************************************************************************/
+package io.github.dsheirer.dsp.am;
+
+import io.github.dsheirer.sample.Listener;
+import io.github.dsheirer.sample.complex.ComplexBuffer;
+import io.github.dsheirer.sample.real.RealBuffer;
+
+public class AMDemodulator_CB extends AMDemodulator implements Listener<ComplexBuffer>
+{
+	private Listener<RealBuffer> mListener;
+	
+	public AMDemodulator_CB( float gain )
+	{
+		super( gain );
+	}
+	
+	@Override
+	public void receive( ComplexBuffer buffer )
+	{
+		if( mListener != null )
+		{
+			float[] samples = buffer.getSamples();
+			
+			int half = samples.length / 2;
+			
+			float[] demodulated = new float[ half ];
+
+			for( int x = 0; x < half; x++ )
+			{
+				int index = x * 2;
+				
+				demodulated[ x ] = demodulate( samples[ index ], samples[ index + 1 ] );
+			}
+			
+			mListener.receive( new RealBuffer( demodulated ) );
+		}
+	}
+	
+	public void setListener( Listener<RealBuffer> listener )
+	{
+		mListener = listener;
+	}
+
+	public void removeListener()
+	{
+		mListener = null;
+	}
+
+	public void dispose()
+	{
+		mListener = null;
+	}
+}