add toString() methods for easier debug


git-svn-id: https://svn.apache.org/repos/asf/ant/ivy/core/trunk@1553589 13f79535-47bb-0310-9956-ffa450edef68
Initialize with the default environment profile provider


git-svn-id: https://svn.apache.org/repos/asf/ant/ivy/core/trunk@1553590 13f79535-47bb-0310-9956-ffa450edef68