title: Change Default Calendar of CultureAndRegionInfoBuilder
body: <p>I want to change the default calender of 'th-TH' culture from ThaiBuddhist to Gregorian and register it as a custom culture.</p>
  
  <pre><code>CultureAndRegionInfoBuilder cultureAndRegionInfoBuilder = new CultureAndRegionInfoBuilder("th-TH", CultureAndRegionModifiers.Replacement);
  cultureAndRegionInfoBuilder.AvailableCalendars = new Calendar[] { new GregorianCalendar()};
  cultureAndRegionInfoBuilder.Register();
  </code></pre>
  
  <p>Above segment does not change the default calendar.</p>
  
  <pre><code>CultureInfo cultureInfo = new CultureInfo("th-TH");
  cultureInfo.DateTimeFormat.Calendar = new GregorianCalendar();
  
  CultureAndRegionInfoBuilder cultureAndRegionInfoBuilder = new CultureAndRegionInfoBuilder("th-TH", CultureAndRegionModifiers.Replacement);
  cultureAndRegionInfoBuilder.LoadDataFromCultureInfo(cultureInfo);
  
  cultureAndRegionInfoBuilder.Register();
  </code></pre>
  
  <p>This does not work either.</p>
  
  <p>Please help. Thanx</p>