Ergonomic ResponseError via derive macro

[Brayan-724]

I actually use actix_failwrap crate (previously actix_error_proc), it adds some macros that make error management so easy, similar to how ResponseError works, but that crate don't use ResponseError so I think it would be good to have similar macros built-in. Currently, I will be using my fork of actix_failwrap that uses ResponseError.

This is how it would be (the example is pretty invalid/silly):

#[derive(ResponseError, thiserror::Error, Debug)]
#[status_code(InternalServerError)]
// maybe with transformers like the crates mentioned
// (so good to standarize responses)
#[transform_response(json_schema)]
pub enum LoginError {
	#[error("Either the email or the password is invalid. Please check the input credentials")]
	#[status_code(Unauthorized)]
	InvalidCredentials,
	#[error("Error decoding jwt: {0}")]
	JwtDecode(#[from] jsonwebtoken::errors::Error),
}

fn decode_jwt(..) -> Result<UserData, jsonwebtoken::errors::Error>;

#[post("/login")]
pub fn login(..) -> Result<UserToken, LoginError> {
  let data = decode_jwt(..)?;
  data.validate(..)?;

  Ok(..)
}