rgw:send x-amz-version-id header when upload files

rgw:send x-amz-version-id header when upload files

To be compatible with aws s3, an x-amz-version-id header should be returned.

For atomic upload, RGWPutObj::version_id will stores the version-id either
generated by rgw randomly or read from user. For multipart upload,
RGWCompleteMultipart::version_id will stores the version-id either
generated by rgw randomly or read from user.

Function send_respones() will send 'x-amz-version-id' header when version_id is not empty.

Signed-off-by: Xinying Song <songxinying@cloudin.cn>
(cherry picked from commit b4a937562a7ae909c2748980b5327189ccb8cdc0)