default index page: added our openresty blog site.

html/index.html

@@ -15,8 +15,8 @@
 <p>If you see this page, the OpenResty web platform is successfully installed and
 working. Further configuration is required.</p>
 
-<p>For online documentation and support please refer to
-<a href="https://openresty.org/">openresty.org</a>.<br/>
+<p>For online documentation and support please refer to our
+<a href="https://openresty.org/">openresty.org</a> site and <a href="https://blog.openresty.com/">our official blog</a>.<br/>
 Commercial support is available at
 <a href="https://openresty.com/">openresty.com</a>.</p>