title: Ignited Datatable add column for auto increment field
body: <p>I follow <a href="http://www.ahmed-samy.com/php-codeigniter-full-featrued-jquery-datatables-part-1/" rel="nofollow">this</a> tutorial and it works, but how to add <strong>No</strong> field which is <em>autoincrement</em></p>
  
  <pre><code>No | date              | total_sent_status|
  ---+-------------------+------------------+
  1  |2013-12-26 00:00:00|         3        |
  ---+-------------------+------------------+
  2  |2018-10-21 00:00:00|         3        |
  ---+-------------------+------------------+
  </code></pre>
  
  <p><strong>Note:</strong> </p>
  
  <p>the <strong>No</strong> record is a php looping not record from database
  before I used Ignited Datatables, but now Im stuck, is anyone have the same 
  experience before? thank you</p>