message: Cleared image when prop removed or cleared
diff: - (void)setImage:(RCTImageSource *)source
  {
  + if (!!source) {
  [[_bridge moduleForName:@"ImageLoader"] loadImageWithURLRequest:source.request callback:^(NSError *error, UIImage *image) {
  dispatch_async(dispatch_get_main_queue(), ^{
  self -> _image = image;
  self -> _button.image = image;
  });
  }];
  + } else {
  + _image = nil;
  + _button.image = nil;
  + }
  }
  - (void)setSystemItem:(UIBarButtonSystemItem)systemItem
  