[Nix-dev] --ignore-liveness when nix-store --delete'ing

[stewart mackenzie]

Some more information:

$ sudo nixos-rebuild --rollback switch
switching from generation 223 to 222
/nix/var/nix/profiles/per-user/root/channels/nixos/nixpkgs/nixos/modules/installer/tools/nixos-rebuild.sh:
line 237: /nix/var/nix/profiles/system/bin/switch-to-configuration: No
such file or directory
warning: error(s) occured while switching to the new configuration