Issue 266: error handling in chunksUploaded()
Addresses issue https://gitlab.com/meno/dropzone/-/issues/266
Allow the callback in chunksUploaded() to take an error message that indicates the upload has failed in the final processing of the chunks.
Addresses issue https://gitlab.com/meno/dropzone/-/issues/266
Allow the callback in chunksUploaded() to take an error message that indicates the upload has failed in the final processing of the chunks.