Place all modules in either:
- `modules/${manager}/${module}.nix`
- `modules/${manager}/${module}/default.nix`
- `${manager}` - One of `nixos`, `nix-on-droid`, `nix-darwin` or `home-manager`
- `${module}` - Module name (autoimported by configurations, used for exporting)
Fix `hasDirectories`
Correctly detect `autoDarwinConfigurations` (did not check for `home`)
Decrease usage of `with`
Depend more on `lib` functions over custom implementations
Reindent correctly some code