Pinch zoom stopped working on 2.0.0

The pinch zoom or double click zoom seemed to have stopped working after updating to 2.0.0 worked 100% on v1.3.1

Any ideas would be helpful please!

```
public class ZoomableImageViewTarget extends ImageViewTarget {
public ZoomableImageViewTarget(ImageView view) {
super(view);
}

@Override
public void onResourceReady(Drawable resource, @Nullable Transition transition) {
super.onResourceReady(resource, transition);

PhotoViewAttacher photoViewAttacher = new PhotoViewAttacher(view);
photoViewAttacher.setZoomable(true);
photoViewAttacher.update();
}

@Override
protected void setResource(@Nullable Drawable resource) {
}
}
```