Better OpenSLES backend implementation for Android

- Uses buffer values gleaned from Android system
    - Removes completely unnecessary playq and uses ringBuffer instead with read/write heads
    - ringBuffer includes a certain amount of "overflow" space for callback convenience

Android/app/src/main/java/org/deadc0de/apple2ix/DevicePropertyCalculator.java

@@ -84,7 +84,7 @@ public final class DevicePropertyCalculator
 
             SR_CHECK = am.getProperty( AudioManager.PROPERTY_OUTPUT_SAMPLE_RATE );
         }
-        final int defaultSampleRate = 44100;
+        final int defaultSampleRate = 22050;
 
         return ( SR_CHECK != null ) ? Integer.parseInt( SR_CHECK ) : defaultSampleRate;
     }