title: Constrain Mapbox panning north/south only?
body: <p>Anyone know how to constrain the panning in a Mapbox map only using north/south bounds? What I would like to do is use the world copy so that users can continuously pan east to west, but restrict the north and south panning so that you can't pan outside of the map tiles (which I find super annoying). I'm currently using a maxbounds when initializing the map to prevent panning into the white tiles above and below the poles, but that's a no-go with world copying.</p>