This implements NixOS/rfcs#136. This issue is agreed-upon by the https://github.com/orgs/NixOS/teams/nix-team

Required changes:

• rename to nix store info
• return bool or null for the trusted field instead of currently int
  • if the underlying enum is converted to an enum struct, the potential to make this mistake will dissapear
• ensure that --json output fits the JSON guidelines