Batch process messages

[cdekok]

Allow event listeners to batch process messages by using a list type, amount of messages to be processed will depend on event types and amount specified in the consumer.

/**
 * Batch process messages
 */
class BatchListener : EventListener {
    @EventHandler
    fun on(event: List<RecordCreated>) {
        logger.info { "handle record created ${event.size}" }
    }
}