version: Extend /etc/os-release

- Provide additional link for support and bug reporting.
- Use HTTPS links (related: "The IAB encourages all web servers to
employ TLS to protect their content, and use OCSP stapling to improve
the efficiency and privacy of revocation checking." [0].
- Add VERSION_CODENAME

[0]: https://www.iab.org/documents/correspondence-reports-documents/2017-2/iab-statement-on-ocsp-stapling/

nixos/modules/misc/version.nix

@@ -106,9 +106,12 @@ in
         NAME=NixOS
         ID=nixos
         VERSION="${config.system.nixosVersion} (${config.system.nixosCodeName})"
+        VERSION_CODENAME=${toLower config.system.nixosCodeName}
         VERSION_ID="${config.system.nixosVersion}"
         PRETTY_NAME="NixOS ${config.system.nixosVersion} (${config.system.nixosCodeName})"
-        HOME_URL="http://nixos.org/"
+        HOME_URL="https://nixos.org/"
+        SUPPORT_URL="https://nixos.org/nixos/support.html"
+        BUG_REPORT_URL="https://github.com/NixOS/nixpkgs/issues"
       '';
 
   };