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/buffer/DoubleCircularBuffer.java

@@ -0,0 +1,80 @@
+/*******************************************************************************
+ *     SDR Trunk 
+ *     Copyright (C) 2014 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.buffer;
+
+import java.util.Arrays;
+
+/**
+ * Circular sample buffer - allocates a buffer and stores samples in a circular
+ * fashion, overwriting older samples with newly arrived samples.  Initially
+ * fills buffer with 0-valued samples
+ * 
+ * Can be used as a delay-type buffer, to delay samples by the 'size' amount
+ */
+public class DoubleCircularBuffer
+{
+	double[] mBuffer;
+	int mBufferPointer = 0;
+	
+	public DoubleCircularBuffer( int size )
+	{
+		mBuffer = new double[ size ];
+		
+		Arrays.fill( mBuffer, 0.0 );
+	}
+
+	/**
+	 * Puts the new value into the buffer and returns the oldest buffer value
+	 * that it replaced
+	 * @param newValue
+	 * @return
+	 */
+	public double get( double newValue )
+	{
+		double oldestSample = mBuffer[ mBufferPointer ];
+
+		mBuffer[ mBufferPointer ] = newValue;
+		
+		mBufferPointer++;
+		
+		if( mBufferPointer >= mBuffer.length )
+		{
+			mBufferPointer = 0;
+		}
+		
+		return oldestSample;
+	}
+
+	/**
+	 * Returns the maximum from the values currently in the buffer
+	 */
+	public double max()
+	{
+		double max = 0.0d;
+		
+		for( int x = 0; x < mBuffer.length; x++ )
+		{
+			if( mBuffer[ x ] > max )
+			{
+				max = mBuffer[ x ];
+			}
+		}
+		
+		return max;
+	}
+}