title: What are the options for 'Date.toLocaleString()'?
body: <p>According to the <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Date/toLocaleString" rel="noreferrer">MDN documentation</a> for <code>Date.toLocaleString()</code>, the second parameter is an <code>options</code> parameter:</p>
  <pre class="lang-js prettyprint-override"><code>toLocaleString(locales, options)
  </code></pre>
  <p>Which they use in an example:</p>
  <p><div class="snippet" data-lang="js" data-hide="false" data-console="true" data-babel="false">
  <div class="snippet-code">
  <pre class="snippet-code-js lang-js prettyprint-override"><code>let date = new Date(Date.UTC(2012, 11, 20, 3, 0, 0));
  
  // Request a weekday along with a long date
  let options = { weekday: 'long', year: 'numeric', month: 'long', day: 'numeric' };
  
  console.log(date.toLocaleString('de-DE', options));</code></pre>
  </div>
  </div>
  </p>
  <p>My question is, what are the possible properties for the <code>options</code> parameter?</p>