Update new typeahead method docs to be a bit clearer.

docs/javascript.html

@@ -1493,8 +1493,8 @@ $('.carousel').carousel({
              <tr>
                <td>updater</td>
                <td>function</td>
-               <td>updates input with selection</td>
-               <td>Method used to update input contents. Accepts a single argument <code>item</code> and has the scope of the typeahead instance. Should return a string.</td>
+               <td>replaces contents of text input with typeahead selection</td>
+               <td>Method used to update contents of text input. Accepts a single argument, the <code>item</code> selected from the typeahead, and has the scope of the typeahead instance. Should return a string.</td>
              </tr>
             </tbody>
           </table>