title: Google Maps MarkerLabel is not a function
body: <p>I'm trying to figure out how to add a <a href="https://developers.google.com/maps/documentation/javascript/3.exp/reference#MarkerLabel" rel="noreferrer">Google Maps MarkerLabel</a>.</p>
  
  <p>I'm able to get a standard marker to display, but when I try to add a <code>!</code> label to the marker, I get <code>google.maps.MarkerLabel is not a function</code>.</p>
  
  <pre><code>var marker = new google.maps.Marker({
      animation: google.maps.Animation.DROP,
      label: new google.maps.MarkerLabel({
          text: '!'
      }),
      map: myMap,
      position: myMapOptions.center
  });
  </code></pre>
  
  <p>I'm guessing I can't instantiate a new MarkerLabel object this way. What am I supposed to do to get an exclamation point <em>inside</em> the marker.</p>