Upgrade http crate to 1.0, fix examples

[quasiyoke]

While testing to get dav-server-rs working with a recent axum release, @themasch encountered some problems because axum was using http@1.0, while dav-server-rs was still based on http@0.2.3.

Since the 1.0 release of http brings some stability and backward compatibility promises, @themasch figured it might be worth updating to the new release so this library is ready to be used with recent releases of all the frameworks building on http.

@themasch fixed up the hyper examples (the latest hyper release dropped some QoL features which bloats the example a bit).

I've fixed the actix and warp examples by adding some compatibility code while they remain on older versions of hyper and http. Upgrade issues:

• actix
• warp

[messense]

Thanks a lot!