Refactor dependencies to reduce code base size (#111)

Use crates to reduce code base size :

* `actix-remote-ip` to safely determine user IP location
* `light-openid` for the OpenID primitives & as client to handle federation

Reviewed-on: #111

src/controllers/login_api.rs

@@ -1,9 +1,9 @@
 use crate::actors::users_actor;
 use crate::actors::users_actor::UsersActor;
 use crate::data::action_logger::{Action, ActionLogger};
-use crate::data::remote_ip::RemoteIP;
 use actix::Addr;
 use actix_identity::Identity;
+use actix_remote_ip::RemoteIP;
 use actix_web::{web, HttpRequest, HttpResponse, Responder};
 use webauthn_rs::prelude::PublicKeyCredential;