#6 DMR Decoder (#947)

* #6 DMR decoder feature - work in progress

* #6 DMR Decoder.

* #6 DMR Decoder.  Code review updates.

Co-authored-by: Zhenyu Mao <maozhenyu@foxmail.com>
Co-authored-by: Denny <denny@denny-desktop>

src/main/java/io/github/dsheirer/source/Source.java

@@ -85,11 +85,6 @@ public abstract class Source extends Module implements ISourceEventListener, ISo
      */
     public abstract long getFrequency();
 
-    /**
-     * Process any cleanup actions to prepare for garbage collection of this source
-     */
-    public abstract void dispose();
-
     /**
      * Registers the listener to receive overflow state changes.  Use null argument to clear the listener
      */