Make sleep delay configurable for debugging

git-svn-id: https://svn.apache.org/repos/asf/sling/trunk@1489412 13f79535-47bb-0310-9956-ffa450edef68
Switch to JUnit 4 style

git-svn-id: https://svn.apache.org/repos/asf/sling/trunk@1489413 13f79535-47bb-0310-9956-ffa450edef68