title: Jquery, Ajax, php, Datatable UTF-8 encoding issue
body: <p>I am using DataTabels with PHP, AJAX, jQuery.</p>
  
  <p>I get some data from MySQL database and when it contains some specific characters, then it crashes (characters like ä ü õ etc).</p>
  
  <p>Here is where I "fetch data" to my table: </p>
  
  <pre><code>function fetch_data()
  {
     var dataTable = $('#user_data').DataTable({
       "processing" : true,
       "serverSide" : true,
       "order" : [],
       "ajax" : {
         url:"fetch.php",
         type:"POST"
       }
     });
  }
  </code></pre>
  
  <p>and this is my <code>fetch.php</code> where I make the output : </p>
  
  <pre><code>$output = array(
   "draw"    =&gt; intval($_POST["draw"]),
   "recordsTotal"  =&gt;  get_all_data($connect),
   "recordsFiltered" =&gt; $number_filter_row,
   "data"    =&gt; $data
  );
  
  echo json_encode($output);
  </code></pre>
  
  <p>I tried to add </p>
  
  <pre><code>contentType: "application/json; charset=utf-8",
  dataType: "json",
  </code></pre>
  
  <p>To <code>fetch_data</code> function, but then my result just went empty... Where am I wrong?</p>