title: mapbox marker rotation/bearing
body: <p>is there any chance to set the rotation for a marker? For now, I set the map bearing to the angle of one marker, but the others should have their own marker bearing.</p>
  
  <p>At the moment, I'm using the marker definition like so:</p>
  
  <pre><code>var marker_el = document.createElement('div');
  marker_el .className = 'marker';
  var new_marker = new mapboxgl.Marker(marker_el)
      .setPopup(marker_PopUp);
  </code></pre>
  
  <p>and set it to the map:</p>
  
  <pre><code>new_marker.setLngLat([lon, lat]);
  new_marker.addTo(map);
  </code></pre>
  
  <p>I'm using JS and react and for the map mapbox-gl</p>