OAK-51 : Access Control Management (tests, minor improvement)

git-svn-id: https://svn.apache.org/repos/asf/jackrabbit/oak/trunk@1470949 13f79535-47bb-0310-9956-ffa450edef68
OAK-758 : Implement AC-editing by principal (Jackrabbit API)

git-svn-id: https://svn.apache.org/repos/asf/jackrabbit/oak/trunk@1470950 13f79535-47bb-0310-9956-ffa450edef68