title: Get record type labels as a list of strings
body: <p>Is it possible to get the labels of a record type as a list of strings? 
  For example, given the following type:</p>
  
  <pre><code>type Person = {
      Name: string
      Age: int
  }
  </code></pre>
  
  <p>I want a function that gives me <code>["Name"; "Age";]</code></p>