Previously minio gateway returns invalid bucket name error for invalid
meta data. This is fixed by returning BadRequest with 'Unsupported
metadata' in response.
Fixes#4891
Previously if any multipart part size > 100MiB is uploaded, azure
gateway returns error.
This patch fixes the issue by creating sub parts sizing each 100MiB of
given multipart part. On complete multipart, it fetches all uploaded
azure block ids for each parts and performs completion.
Fixes#4868
Bala FA