Adding a link to the API documentation of BCEL 5.2 to the left navi bar

git-svn-id: https://svn.apache.org/repos/asf/commons/proper/bcel/trunk@1535951 13f79535-47bb-0310-9956-ffa450edef68
Make sure the site publish does not remove API docs of old releases

git-svn-id: https://svn.apache.org/repos/asf/commons/proper/bcel/trunk@1535952 13f79535-47bb-0310-9956-ffa450edef68