S3Proxy 3.3.0

• Add openstack-swift-sdk storage backend, #1095
• Enforce part checksums in CompleteMultipartUpload, #656
• Fix ListObjects hiding user objects with UUID-shaped keys, #1089
• Fix v4 signatures when using service path, #845
• Improve nio2 directory marker S3 compatibility, #1093
• Stream azureblob single-part PUT to avoid heap exhaustion, #1090
• Validate x-amz-checksum-{crc32,crc32c,sha1,sha256} headers, #765

Note that this is the last release to rely on Apache jclouds. Future releases will lack its Atmos and B2 storage backends.

Thanks @craffit and @mmieszczak for opening pull requests to improve S3Proxy!