title: SCNText with SCNLookAtConstraint looking the wrong way
body: <p>I want to display text alongside my 3D model using SceneKit in iOS. It just has to appear like it is 2D. So the text should always be facing the camera, however I rotate the 3D model. I have an <code>SCNNode</code> with a <code>SCNText</code> geometry and I attached an <code>SCNLookAtConstraint</code> like so:</p>
  
  <pre><code>let constraint = SCNLookAtConstraint(target: cameraNode)
  constraint.gimbalLockEnabled = true
  textNode.constraints = [constraint]
  </code></pre>
  
  <p>They seem to be facing the camera, but only the wrong way! I see all text mirrored! Also, sometimes the text rotates, I want it to be aligned horizontally at all times. So this is all the behaviour I don't want.</p>
  
  <p>Can somebody help me out here? I just want to have some text that follows a few nodes in my 3D object. I don't care how. It doesn't have to be SCNText for all I care, if this can be done with a simple UILabel: fine with me! Just tell me how!</p>