anchor.diff:  
           start_seq = StartSeq,
           history = History,
  +        session_id = couch_uuids:random(),
           source_log = SourceLog,
           target_log = TargetLog,
           rep_starttime = httpd_util:rfc1123_date(),
  
positive.code: 
      start_seq,
      history,
      source_log,
      target_log,
      rep_starttime,
  
negative.code:         committed_seq = NewSeqNum,
          start_seq = StartSeqNum,
          history = OldHistory,
          session_id = SessionId,
          source_log = SourceLog,
          target_log = TargetLog,
          rep_starttime = ReplicationStartTime,
  