Adding zee editor to nixpkgs

[booklearner]

Hey! For anyone else using nix, I've created a PR to add the zee editor to the package repositories.

NixOS/nixpkgs#185449

[kevinmatthes]

Thank you, @booklearner! I just opened an issue about a new release such that the progress since version 0.3.2 can be made accessible for everyone from the official package registries.

[booklearner]

Nice (reference: #92). Feel free to ping me when there's some traction and I'd be happy to keep the nix package up to date!