OAK-51 : Access Control Management (wip)

git-svn-id: https://svn.apache.org/repos/asf/jackrabbit/oak/trunk@1469727 13f79535-47bb-0310-9956-ffa450edef68
OAK-776: NodeState convenience accessors
Revert changes from revision 1469396 to avoid circular dependency between packages spi.state and plugins.memory.

git-svn-id: https://svn.apache.org/repos/asf/jackrabbit/oak/trunk@1469728 13f79535-47bb-0310-9956-ffa450edef68
OAK-527: permissions (wip, tests)

git-svn-id: https://svn.apache.org/repos/asf/jackrabbit/oak/trunk@1469729 13f79535-47bb-0310-9956-ffa450edef68