* Add InvalidRangeSpec error
* Add EntityTooSmall to from_u32
* Add InvalidRangeSpec to from_u32
* Map InvalidRangeSpec to correct S3ErrorCode
* Return Error::InvalidRangeSpec
* Use auto implementation
* Add default storage class to ListObjectsV2
Resolves#764
* Add storage_class to response
* Make storage class optional so default won't be an empty string
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Co-authored-by: houseme <housemecn@gmail.com>