s3: document --ignore-checksum workaround for KMS #1824
s3: document --ignore-checksum workaround for KMS #1824

ncw/rclone,ncw/rclone,yonjah/rclone,yonjah/rclone,yonjah/rclone,ncw/rclone,seuffert/rclone,seuffert/rclone,B4dM4n/rclone,seuffert/rclone,olihey/rclone,seuffert/rclone,olihey/rclone,olihey/rclone,B4dM4n/rclone,B4dM4n/rclone,ncw/rclone,olihey/rclone,B4dM4n/rclone,yonjah/rclone