I wanted a nicer way to declare error enums in my project, so I give you `error_mancer`
Cargo.io: https://crates.io/crates/error\\\_mancer
This crate lets you easily define error enums using a simple macro, it provides custom error messages when a error is attempted to be returned without being listed, and also works with \anyhow\\ and friends (in which case the enum will always be private, but its useful for when implementing traits that require a generic result type, but you want to restrict yourself)
