OAK-168: Basic JCR VersionManager support
OAK-601: Node#getVersionHistory fails with UnsupportedRepositoryOperationException
OAK-602: VersionManager is never updated
- Resume work on JCR versioning
- Enable tests for OAK-601 and OAK-602 again and remove workarounds in tests
- Take protected status into account in Node.canAddMixin()

git-svn-id: https://svn.apache.org/repos/asf/jackrabbit/oak/trunk@1479831 13f79535-47bb-0310-9956-ffa450edef68