title: Removing object from Group removes object from Scene
body: <p>I have a ThreeJS Group object that contains objects in the scene. I can add these objects fine and manipulate them independently, but whenever I try to remove an object from the group, it gets deleted from the scene.  </p>
  
  <pre><code>var group=this.scene.getObjectByName(id);
  for (var i=group.children.length-1; i &gt;= 0; --i)            
      group.remove(group.children[i]);
  </code></pre>