CURATOR-140: Allow InterProcessReadWriteLock consumer to set lock node d...

Simple change to plumb through the ability to set node data from the consumer of InterProcessReadWriteLock.
Ok, just wasn't obvious because there's no explicit assert checking that the data in the InterProcessReadWriteLock is different to the mutated nodeData array. I notice that there's no way of getting this data out of the InterProcessReadWriteLock to do an explicit assert though, so I think that this is fine.