Support for Amazon S3: Multipart Upload

[nerg4l]

Amazon S3 has a functionality named Multipart Upload. With this support the library could use S3 storage drivers.

• Article about the service
• Uploading objects using multipart upload API

[nerg4l]

A detailed explanation from tus.io about the issues they faced when they added S3 support: https://tus.io/blog/2016/03/07/tus-s3-backend.html