Migrated RewardsApprovalTest

Work done
1) Added persistence.xml for task persistence
2) Added log4j.xml which turns off ugly WARN messages produced by BTM and Hibernate
3) Migrated RewardsApprovalTest

Todo
1) RewardsApprovalTest - 'john' is probably not part of HR group as getTasksAssignedAsPotentialOwner does not return anything. It works for 'mary' no problem.