title: Is there a way to get the list of available locales in PHP?
body: <p>In Java, you can call <code>Locale.getAvailableLocales()</code> to get the list of available locales.</p>
  
  <p>I was expecting an equivalent from the PHP <a href="http://php.net/manual/en/class.locale.php" rel="noreferrer">Locale</a> class, but could not find one.</p>
  
  <p>Is there a way to get an array of all valid Locales?</p>