creating temporary directory with a unique name

git-svn-id: https://svn.apache.org/repos/asf/ant/core/trunk@1585372 13f79535-47bb-0310-9956-ffa450edef68
changing tests to adopt unique temporary directories

git-svn-id: https://svn.apache.org/repos/asf/ant/core/trunk@1585377 13f79535-47bb-0310-9956-ffa450edef68
Upstream merge