Adds generated content

git-svn-id: https://svn.apache.org/repos/asf/struts/site@1566266 13f79535-47bb-0310-9956-ffa450edef68
Converts announce to Markdown and Jekyll

git-svn-id: https://svn.apache.org/repos/asf/struts/site@1566267 13f79535-47bb-0310-9956-ffa450edef68