Transfer nixy to nix-community

[cuskiy]

Hello,

I’d like to propose moving nixy to nix-community.
nixy

This is my project. It's currently stable. I think it could provide a useful and unique building block for the nix ecosystem and fit well within nix-community.

[zowoq]

We prefer that projects have matured a little before they are moved.

[cuskiy]

Thanks.