ISSUE #155: Update home page banner

Descriptions of the changes in this PR:

Update home page banner

Author: Jia Zhai <zhaijia@apache.org>

Reviewers: Sijie Guo <sijie@apache.org>

This closes #162 from zhaijack/update_banner, closes #155
diff --git a/website/index.md b/website/index.md
index b808e87..e7d49f8 100644
--- a/website/index.md
+++ b/website/index.md
@@ -5,7 +5,7 @@
 <div class="alert alert-info alert-dismissible" role="alert">
 <span class="glyphicon glyphicon-flag" aria-hidden="true"></span>
 <button type="button" class="close" data-dismiss="alert" aria-label="Close"><span aria-hidden="true">&times;</span></button>
-The Apache DistributedLog project is in the process of bootstrapping. This includes the website -- so please file issues you find in <a href="/community">Jira</a>. Thanks!
+Apache DistributedLog graduated from Apache Incubator and is a sub-project of Apache BookKeeper now!
 </div>
 
 <!-- landing page -->