[WIP] Creates a new AFSK-1200 correlation decoder and updates the

Fleetsync II decoder to use it.  Adds instrumented version of the decoder
and a new Fleetsync2 FX pane to the DemodulatorViewerFX tool.

Note: the remaining AFSK-1200 based decoders will all be ported to use
this new AFSK1200 decoder (MDC1200, Tait1200, LowJack1200).

src/main/java/io/github/dsheirer/module/decode/afsk/AbstractAFSKDecoder.java

@@ -0,0 +1,61 @@
+/*******************************************************************************
+ * sdr-trunk
+ * Copyright (C) 2014-2018 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.module.decode.afsk;
+
+import io.github.dsheirer.dsp.afsk.AFSK1200Decoder;
+import io.github.dsheirer.module.decode.Decoder;
+import io.github.dsheirer.sample.Listener;
+import io.github.dsheirer.sample.buffer.IReusableBufferListener;
+import io.github.dsheirer.sample.buffer.ReusableBuffer;
+
+/**
+ * Abstract class for Audio Frequency Shift Keying (AFSK) 1200-baud decoder based decoder modules.
+ *
+ * This class handles the AFSK 1200 decoder and incoming sample stream buffer management.
+ *
+ * Sub-class implementations should invoke getDecoder().setListener() to receive decoded symbol stream.
+ */
+public abstract class AbstractAFSKDecoder extends Decoder implements IReusableBufferListener, Listener<ReusableBuffer>
+{
+    private AFSK1200Decoder mAFSK1200Decoder;
+
+    public AbstractAFSKDecoder(AFSK1200Decoder decoder)
+    {
+        mAFSK1200Decoder = decoder;
+    }
+
+    public AbstractAFSKDecoder(AFSK1200Decoder.Output output)
+    {
+        mAFSK1200Decoder = new AFSK1200Decoder(output);
+    }
+
+    protected AFSK1200Decoder getDecoder()
+    {
+        return mAFSK1200Decoder;
+    }
+
+    @Override
+    public void receive(ReusableBuffer reusableBuffer)
+    {
+        mAFSK1200Decoder.receive(reusableBuffer);
+    }
+
+    @Override
+    public Listener<ReusableBuffer> getReusableBufferListener()
+    {
+        return this;
+    }
+}