add long press action for action image

iOSClient/Library/MWPhotoBrowser/MWPhotoBrowser.m

@@ -191,6 +191,10 @@ static void * MWVideoPlayerObservation = &MWVideoPlayerObservation;
         [self.view addGestureRecognizer:swipeGesture];
     }
     
+    // Long Press
+    UILongPressGestureRecognizer* longPressRecognizer = [[UILongPressGestureRecognizer alloc] initWithTarget:self action:@selector(actionButtonPressed:)];
+    [self.view addGestureRecognizer:longPressRecognizer];
+    
 	// Super
     [super viewDidLoad];
 }