Fixed a few typos

index.html

@@ -176,7 +176,7 @@ <h2 class="no-num no-toc" id="table-of-contents">Table of Contents</h2>
    <li><a href="#close-on-unload"><span class="secno">8.4 </span>Close on Unload</a></ol></li>
  <li><a href="#security-considerations"><span class="secno">9 </span>Security Considerations</a></li>
  <li><a href="#references" class="no-num">References</a></li>
- <li><a href="#acknowledgments" class="no-num">Acknowledgments</a></ol>
+ <li><a href="#acknowledgements" class="no-num">Acknowledgements</a></ol>
 <!--end-toc-->
 
 <h2 id="introduction"><span class="secno">1 </span>Introduction</h2>
@@ -566,7 +566,7 @@ <h2 class="no-num" id="references">References</h2>
 
 </dl></div>
 
-<h2 class="no-num" id="acknowledgments">Acknowledgements</h2>
+<h2 class="no-num" id="acknowledgements">Acknowledgements</h2>
 
 <p>Thanks to Wayne Carr and Anssi Kostiainen for input, thorough reviews and feedback to this draft.</p>