Add Serde support for Request and Response

[KaiserKarel]

I need to log requests and responses using a structured logger. Having serde behind a feature would help a lot with that. I think these structs are quite fundamental datatypes, and that more users would probably want to store/log them somehow.

[chapa]

Have you tried this crate : https://crates.io/crates/http-serde ?

(I don't, I was just passing by and I saw ~light~ your issue :blush:)

[andrewtoth]

I wrote a crate that lets you serialize and deserialize Request and Response types, as well as the rest of the types. https://crates.io/crates/http-serde-ext