Feature request: Tesla Middleware

[tanguilp]

Thanks for creating this library which is a great addition to our Elixir ecosystem!

As Req plugins cannot support some features (like HTTP caching), because of architecture limitations, it would be great to support a Tesla Middleware as well.

Cheers, and keep up the great work ⭐

[reisub]

Thanks @tanguilp, I'll look into this.

[reisub]

@tanguilp can you give the code in #8 a spin please?

Let me know what you think, I don't use Tesla myself so I'm not sure if I'm missing something important.