basic logical replication support for the disorder tests

add in support to the setupReplication function to create some nodes
as being 'logical'
add in a very basic 'logical replication' test

Make this the only disorder test enabled on this branch
sending feedback to the walsender if we can't lock the mutex

If the remoteWorker has the connection lock and is in the middle
of a COPY (or other long running operation) we don't want to stop
sending feedback.  Loop around attempting to get the lock and send
feedback