Add rel=nofollow to some external links

git-svn-id: https://svn.apache.org/repos/asf/forrest/trunk@595294 13f79535-47bb-0310-9956-ffa450edef68
diff --git a/site-author/content/xdocs/thanks.xml b/site-author/content/xdocs/thanks.xml
index c42bfe9..cf3982a 100644
--- a/site-author/content/xdocs/thanks.xml
+++ b/site-author/content/xdocs/thanks.xml
@@ -60,9 +60,9 @@
       <p>
         Developers use various tools to assist with their work, such as
         <a href="site:catalog">xml editors</a> and IDEs such as
-        <a href="http://www.jetbrains.com/idea/opensource/">IntelliJ IDEA</a> or
-        <a href="http://www.eclipse.org/">Eclipse</a>. Most tools do not require
-        attribution, but some do (<a href="http://www.yourkit.com/">YourKit Java
+        <a href="http://www.jetbrains.com/idea/opensource/" rel="nofollow">IntelliJ IDEA</a> or
+        <a href="http://www.eclipse.org/" rel="nofollow">Eclipse</a>. Most tools do not require
+        attribution, but some do (<a href="http://www.yourkit.com/" rel="nofollow">YourKit Java
         Profiler</a>).
       </p>
     </section>