document .hyphens() mixin

docs/less.html

@@ -907,6 +907,11 @@
         <td><code>@columnCount, @columnGap: @gridGutterWidth</code></td>
         <td>Make the content of any element use CSS3 columns</td>
       </tr>
+      <tr>
+        <td><code>.hyphens()</code></td>
+        <td><code>@mode: auto</code></td>
+        <td>CSS3 hyphenation when you want it (includes <code>word-wrap: break-word</code>)</td>
+      </tr>
     </tbody>
   </table>
   <h3>Backgrounds and gradients</h3>