330 WIP - updates the demodulator viewer with an eye diagram and symbol

chart.  Testing various configurations to see which yields the best
PLL and symbol timing locks.

src/main/java/io/github/dsheirer/source/wave/ComplexWaveSource.java

@@ -167,13 +167,8 @@ public class ComplexWaveSource extends ComplexSource implements IControllableFil
         if(mInputStream != null)
         {
             mInputStream.close();
+            mInputStream = null;
         }
-        else
-        {
-            throw new IOException("Can't close wave source - was not opened");
-        }
-
-        mInputStream = null;
     }
 
     /**