Add reference other formats.

Author: fredericDelaporte

doc/index.html

@@ -3,7 +3,13 @@
 title: Documentation
 ---
 <ul>
-	<li><a href="/doc/nhibernate-reference/index.html">The NHibernate Reference</a></li>
+	<li>
+		<a href="/doc/nhibernate-reference/index.html">The NHibernate Reference</a>
+		(<a href="/doc/nhibernate-reference/index.html">HTML</a>,
+		<a href="/doc/nh/en/index.html">single page HTML</a>,
+		<a href="/doc/nh/en/nhibernate_reference.pdf">PDF</a>,
+		<a href="/doc/nh/en/nhibernate.reference.chm">CHM</a>)
+	</li>
 	<li><a href="/doc/nhibernate-features.html">NHibernate Features</a></li>
 	<li><a href="/doc/tutorials/first-nh-app/your-first-nhibernate-based-application.html">Tutorial: Your first NHibernate based application</a></li>
 </ul>