Update timeline options to include dataAttributes

docs/timeline.html

@@ -378,6 +378,14 @@ var options = {
     When active, a blue shadow border is displayed around the Timeline. The Timeline is set active by clicking on it, and is changed to inactive again by clicking outside the Timeline or by pressing the ESC key.</td>
 </tr>
 
+<tr>
+  <td>dataAttributes</td>
+  <td>Array[String]</td>
+  <td>false</td>
+  <td>An array of fields optionally defined on the timeline items that will be appended as <code>data-</code> attributes to the content element.</td>
+</tr>
+
+
 <tr>
     <td>editable</td>
     <td>Boolean | Object</td>