feat: create a Client constructor to supply the Reqwest::Client

[fusetim]

Create a new constructor with_http_client for tmdb_api::client::Client to supply the inner Reqwest::Client.

I'm not sure the name is well chosen, given the existence of with_base_url, which doesn't follow the same model. Nevertheless, I think it's the only blocking issue with this PR.

Resolve: https://github.com/jdrouet/tmdb-api/issues/35

[jdrouet]

👋 Thanks @fusetim for this PR. After thinking about it, I think I'd have went with a builder pattern.

[fusetim]

Thank you for your reply. Would this new approach suit you?

[jdrouet]

I did a fix and a cleanup PR in #37 😉

[fusetim]

Amazing, thank you 🎉