New crate: with_dir

https://crates.io/crates/with_dir

Hey all, long time follower of this subreddit and rust tinkerer. For the first time this morning I searched crates.io for a crate and it didn’t exist! So I wrote it 😃 very small crate for changing directory and having it change back at the end of scope. Hope it helps someone!

Thanks to the parking_lot crate as well for providing reentrant mutex, allowed me to provide some threading protection that I thought would not be achievable.