title: TFS build get label if exists else latest?
body: <p>I'm specifying a label in the "Get Version" property of a TFS 2012 build definition:</p>
  
  <p>Get Version: LMyLabel</p>
  
  <p>However, if MyLabel doesn't exist, the build fails with this error message:</p>
  
  <p>Exception Message: TF14064: Could not find label MyLabel@*. (type LabelNotFoundException)</p>
  
  <p>How can I configure the build to default to the latest code if MyLabel doesn't exist?</p>