Add icl to root index.html

[SVN r67258]

index.html

@@ -55,7 +55,8 @@
 
   <h3>Changes in this release</h3>
 
-  <p>This release includes ? new libraries
+  <p>This release includes 1 new library
+  (<a href="libs/icl/doc/html/index.html">Interval Container Library</a>)
   as well as updates to many existing libraries. See
   <a href="http://www.boost.org/users/history/version_1_46_0">Release
   History</a> for more information.</p>