Update operation result should include the new value of the node

[dinoboff]

For a write operation newValue holds the the value written to the node getting written; it is the value the user submitted and the value that will get written.

For multi-location write operations, having the patch data is important but having the resulting new value of the node would be useful; the alternative is something like result.newDatabase.root.path.to.node.$value().

I am not sure if the new attribute to the result object should be the resulting node value (minor change) or the patch data (major change if we use newValue for the resulting node value).