properly unbind the service to avoid a ServiceConnection leak

vlc-android/src/org/videolan/vlc/android/AudioActivityGroup.java

@@ -66,5 +66,4 @@ public class AudioActivityGroup extends ActivityGroup {
         AudioServiceController.getInstance().unbindAudioService();
         super.onPause();
     }
-
 }

vlc-android/src/org/videolan/vlc/android/AudioPlayerActivity.java

@@ -145,4 +145,10 @@ public class AudioPlayerActivity extends Activity implements AudioPlayer {
         // mAudioController.shuffle();
         Util.toaster(R.string.notavailable);
     }
+
+    @Override
+    protected void onPause() {
+        AudioServiceController.getInstance().unbindAudioService();
+        super.onPause();
+    }
 }

vlc-android/src/org/videolan/vlc/android/VideoActivityGroup.java

@@ -67,4 +67,9 @@ public class VideoActivityGroup extends ActivityGroup {
         super.onBackPressed();
     }
 
+    @Override
+    protected void onPause() {
+        AudioServiceController.getInstance().unbindAudioService();
+        super.onPause();
+    }
 }