Doesn't work with large batches

[mheffner]

Messages are looked at individually as to whether they exceed the maximum, but a SendMessageBatchRequest might exceed 256kb in aggregate even if none of the individual messages do. It is somewhat confusing given this library appears to support batching.

[PumpMagic]

This just bit me as well. I'd love any solution that minimized calls to SQS / S3 endpoints.

(The logic under question is here.)