HiveStreamingConnection.toString doesn't print transaction batch

HiveStreamingConnection.toString doesn't contain the current transaction state. In hive-hcatalog-streaming, the transaction batch was exposed to the user, which allowed the application to log e.g. transaction id and state when errors occur. Some exceptions from TransactionBatch contain the current transaction id, but many don't.

It would be nice if HiveStreamingConnection.toString also included the currentTransactionBatch.toString.