title: make columns unsortable in dataTables.js jQuery plugin
body: <p>I am using the dataTables.js jQuery plugin.</p>
  
  <p>The first column of my table is a row counter, so I don't want it be sortable by the user. The last column contains some action link that the user can perform on a row.  How can I make these two columns unsortable?</p>
  
  <p>Note: I am using pipeline (server-side process) mode of datatables.</p>