OAK-619 - Lock-free MongoMK implementation

 Adding initial support for node move which simply copies existing node to new path and mark old nodes for deletion

 This impl though would not work well for move of deep node hierarchies.

git-svn-id: https://svn.apache.org/repos/asf/jackrabbit/oak/trunk@1449798 13f79535-47bb-0310-9956-ffa450edef68