as seen by each node.

With metadata option, allow server to return version checksums as well.

To be used by data integrity checker tool.

An S3 server can respond with 200 OK with an S3 Error response for long
standing calls, such as S3 listing when a prefix contains a lot of
entries.

This commit will support this use case. This can only be enabled with
specific calls that return XML as a successful response, so this will not
be confused with GetObject returning a valid document that contains an
S3 error response.

Supported calls: CompleteMultipartUpload and DeleteMultiObjects.