Nix based config

[dwinkler1]

I have created a nix overlay for R.nvim for nix

https://github.com/dwinkler1/r_nvim_nix

Which I am consuming in my neovim setup flake:

https://github.com/dwinkler1/nvimConfig/blob/main/flake.nix

If it is useful to someone I'm happy to create a minimal setup and contribute it here.