OAK-150: Basic JCR LockManager support

Improved tracking of session and open scoped locks and lock tokens
Better interaction between versioning and locking (it's possible to checkin a locked node, not checkout)
Trimmed list of known TCK issues

git-svn-id: https://svn.apache.org/repos/asf/jackrabbit/oak/trunk@1518049 13f79535-47bb-0310-9956-ffa450edef68