title: Getting what is the first day of the week based on Locale with momentJs
body: <p>Using momentJs, is possible to get the first day of the week (Monday(1), Sunday(7)...) based on Locale without creating a new moment?</p>
  
  <p>I know I can access what is the first day of the week for the current locale with:</p>
  
  <pre><code>moment.locale('uk');
  moment().startOf('week').isoWeekday(); //Returns 1
  moment.locale('en');
  moment().startOf('week').isoWeekday(); //Returns 7
  </code></pre>
  
  <p>But I think it's a bit ugly... </p>
  
  <ol>
  <li>Creating a momentjs object.</li>
  <li>Going to the first date of the week. </li>
  <li>Resolving the weekDay.</li>
  </ol>
  
  <p>Any better idea?
  Thx!</p>