adapting code and tests since Apt is not available under JKD1.8 PR 55922

git-svn-id: https://svn.apache.org/repos/asf/ant/core/trunk@1553060 13f79535-47bb-0310-9956-ffa450edef68
adapt documentation. PR 55922

git-svn-id: https://svn.apache.org/repos/asf/ant/core/trunk@1553062 13f79535-47bb-0310-9956-ffa450edef68