WriteLock recipe: incorrect znode ordering when the sessionId is part of the znode name

When the nodes are sorted in WriteLock.java using a TreeSet the whole znode path is taken into account and not just the sequence number.

This causes an issue when the sessionId is included in the znode path because a znode with a lower sessionId will appear as lower than other znode with a higher sessionId even if its sequence number is bigger.

In specific situations this ended with two clients holding the lock at the same time.