📝 add AquaSKK link

Author: mzp

index.html

@@ -35,6 +35,7 @@ <h4>Productivity</h4>
       <li><a href="SnowRabbit/">SnowRabbit</a></li>
       <li><a href="keima/">Keima</a></li>
       <li><a href="FlickSKK/">FlickSKK</a></li>
+      <li><a href="https://github.com/codefirst/aquaskk">AquaSKK(fork)</a></li>
     </ul>
   </div>
   <div class="col-sm-4">