title: VSTS secrets as environment variables
body: <p>In the VSTS build, I set various variables (Edit build -> Variables tab), some I set as secret (click the lock), some I don't.</p>
  
  <p>In the build, I run a command prompt task to run <code>set</code> -- e.g. show me all the environment variables.  Those marked as secret aren't present.</p>
  
  <p>How do I get VSTS secrets into environment variables?</p>