title: Parse cron expression in NCronTab C#
body: <p>I am using <a href="https://www.nuget.org/packages/ncrontab/" rel="nofollow">NCrontab</a> generator in C#. And I want to parse expression which will be start every first Monday , or every third Wednesday, or every second Sunday etc.
  I find some expression <a href="http://cronexpressiondescriptor.azurewebsites.net/?Language=en-US&amp;DayOfWeekStartIndexOne=false&amp;Use24HourFormat=false&amp;VerboseDescription=false&amp;Expression=*%20*%20*%20*%20MON%233" rel="nofollow">like this</a>. But it doesn`t work in NCrontab.</p>
  
  <p>Can you help me with this expression?</p>