Revert "lib: init flakes.nix"

[adisbladis]

Description of changes

This reverts PR #167947.

Flakes aren't standardised and the lib namespace shouldn't be polluted with utilities that serve only experimental uses.

If you want this go participate in the RFC, then come back once the interface is no longer experimental.

Things done

• Built on platform(s)
  • x86_64-linux
  • aarch64-linux
  • x86_64-darwin
  • aarch64-darwin
• For non-Linux: Is sandbox = true set in nix.conf? (See Nix manual)
• Tested, as applicable:
  • NixOS test(s) (look inside nixos/tests)
  • and/or package tests
  • or, for functions and "core" functionality, tests in lib/tests or pkgs/test
  • made sure NixOS tests are linked to the relevant packages
• Tested compilation of all packages that depend on this change using nix-shell -p nixpkgs-review --run "nixpkgs-review rev HEAD". Note: all changes have to be committed, also see nixpkgs-review usage
• Tested basic functionality of all binary files (usually in ./result/bin/)
• 22.05 Release Notes (or backporting 21.11 Release notes)
  • (Package updates) Added a release notes entry if the change is major or breaking
  • (Module updates) Added a release notes entry if the change is significant
  • (Module addition) Added a release notes entry if adding a new NixOS module
  • (Release notes changes) Ran nixos/doc/manual/md-to-db.sh to update generated release notes
• Fits CONTRIBUTING.md.

[sternenseemann]

I don't see why this has to be in nixpkgs . In the light of recent larger changes to lib being rejected until either an RFC about them specifically was accepted, I don't see why adding this has justification.

Since we don't have NixOS/rfcs#82, keeping the flakes lib in a stable release would essentially declare something as stable that is not sure to be (or to stay around even).

[roberth]

If you want this go participate in the RFC, then come back once the interface is no longer experimental.

I sense some frustration here. I know of many reasons why that may be, but not everyone does, and we have to consider that we're in a position of power as maintainers. But alas, maybe I am the one reading too much into this. I'll stop.

RFC 82

Yes please.