activating back javaagent in openejb-core and removing hacks in CmpJarBuilder since we would need to fork too much code from openjpa with current codebase,normally javaagent in a dedicated app classloader should be enough - waiting for side effects on others tests

git-svn-id: https://svn.apache.org/repos/asf/tomee/tomee/trunk@1611208 13f79535-47bb-0310-9956-ffa450edef68