Properly link_to no_icon.png

oedo03/speakers/index.html

@@ -39,7 +39,7 @@ <h2>基調講演</h2>
       <section>
         <ul>
           <li><a href="http://twitter.com/a_matsuda"><img class="gravatar" src="https://www.gravatar.com/avatar/76a777ff80f30bd3b390e275cce625bc"><br>@a_matsuda</a></li>
-          <li><a href="http://twitter.com/koichisasada"><img class="gravatar" src="no_icon.png"><br>@koichisasada</a></li>
+          <li><a href="http://twitter.com/koichisasada"><img class="gravatar" src="../no_icon.png"><br>@koichisasada</a></li>
         </ul>
       </section>
     </section>
@@ -50,7 +50,7 @@ <h2>Ninja Talks</h2>
           <li><a href="http://twitter.com/takkanm"><img class="gravatar" src="https://www.gravatar.com/avatar/8f39a252784d5a99589be6e20c4553fb"><br>@takkanm</a></li>
           <li><a href="http://twitter.com/katsyoshi"><img class="gravatar" src="https://www.gravatar.com/avatar/3fdeea2cc159ff59f9c3306a1e44d8f5"><br>@katsyoshi</a></li>
           <li><a href="http://twitter.com/mrkn"><img class="gravatar" src="https://www.gravatar.com/avatar/f92d08fba5207992c4e6b85ab9515a2f"><br>@mrkn</a></li>
-          <li><a href="http://twitter.com/yuri_at_earth"><img class="gravatar" src="no_icon.png"><br>@yuri_at_earth</a></li>
+          <li><a href="http://twitter.com/yuri_at_earth"><img class="gravatar" src="../no_icon.png"><br>@yuri_at_earth</a></li>
           <li><a href="http://twitter.com/morgan_randy"><img class="gravatar" src="https://www.gravatar.com/avatar/855975ff404621dc525c72b618d95dcc"><br>@morgan_randy</a></li>
           <li><a href="http://twitter.com/hsbt"><img class="gravatar" src="https://www.gravatar.com/avatar/eabad423977cfc6873b8f5df62b848a6"><br>@hsbt</a></li>
           <li><a href="http://twitter.com/yuki24"><img class="gravatar" src="https://www.gravatar.com/avatar/bcd6fc0618a420ba3d59fe5bfaf2b323"><br>@yuki24</a></li>