Header name case-insensitive

[MaGrMo]

Hello according to rfc2616, Message Headers Field names are case-insensitive. I faced with problem that Envoy (CONTOUR) are transforms response headers to lower cases, and clients throws exception "Offset Header Missing" code

Thank you.

[gerdus]

Are you sure you are running the latest version? case-insensitive headers was added in pull request https://github.com/gerdus/tus-dotnet-client/pull/9

I have tested it with envoy proxy and seems to work fine. I have made a commit that adds example docker compose with envoy proxy and examples/tests.