Before this change, when uploading multipart files, onedrive would
sometimes return an unexpected 416 error and rclone would abort the
transfer.
This is usually after a 500 error which caused rclone to do a retry.
This change checks the upload position on a 416 error and works how
much of the current chunk to skip, then retries (or skips) the current
chunk as appropriate.
If the position is before the current chunk or after the current chunk
then rclone will abort the transfer.
See: https://forum.rclone.org/t/fragment-overlap-error-with-encrypted-onedrive/14001Fixes#3131
Nick Craig-Wood
3dfa63b85c