title: Change text on shape
body: <p>Hi
    is it possible to change the text of a shape? I have:</p>
  
  <pre><code>levelFraction = new Text(0, 300, mFont, "text", HorizontalAlign.CENTER);
  </code></pre>
  
  <p>then I add it to the scene:</p>
  
  <pre><code>scene.getTopLayer().addEntity(levelFraction);
  </code></pre>
  
  <p>but I don't see any method to change the text at runtime. Something like:</p>
  
  <pre><code>levelFraction.setText(...);
  </code></pre>
  
  <p>Is that possible?</p>