Rename novaImage to openstackImage

People don't necessary know `nova` is related to Openstack (it is a
component of Openstack). So, it is more explicit to call it
`openstackImage`.

nixos/maintainers/scripts/openstack/nova-image.nix

@@ -1,26 +0,0 @@
-# nix-build '<nixpkgs/nixos>' -A config.system.build.novaImage --arg configuration "{ imports = [ ./nixos/maintainers/scripts/openstack/nova-image.nix ]; }"
-
-{ config, lib, pkgs, ... }:
-
-with lib;
-
-{
-  imports =
-    [ ../../../modules/installer/cd-dvd/channel.nix
-      ../../../modules/virtualisation/nova-config.nix
-    ];
-
-  system.build.novaImage = import ../../../lib/make-disk-image.nix {
-    inherit lib config;
-    pkgs = import ../../../.. { inherit (pkgs) system; }; # ensure we use the regular qemu-kvm package
-    diskSize = 8192;
-    format = "qcow2";
-    configFile = pkgs.writeText "configuration.nix"
-      ''
-        {
-          imports = [ <nixpkgs/nixos/modules/virtualisation/nova-config.nix> ];
-        }
-      '';
-  };
-
-}

nixos/maintainers/scripts/openstack/openstack-image.nix

@@ -0,0 +1,26 @@
+# nix-build '<nixpkgs/nixos>' -A config.system.build.openstackImage --arg configuration "{ imports = [ ./nixos/maintainers/scripts/openstack/openstack-image.nix ]; }"
+
+{ config, lib, pkgs, ... }:
+
+with lib;
+
+{
+  imports =
+    [ ../../../modules/installer/cd-dvd/channel.nix
+      ../../../modules/virtualisation/openstack-config.nix
+    ];
+
+  system.build.openstackImage = import ../../../lib/make-disk-image.nix {
+    inherit lib config;
+    pkgs = import ../../../.. { inherit (pkgs) system; }; # ensure we use the regular qemu-kvm package
+    diskSize = 8192;
+    format = "qcow2";
+    configFile = pkgs.writeText "configuration.nix"
+      ''
+        {
+          imports = [ <nixpkgs/nixos/modules/virtualisation/openstack-config.nix> ];
+        }
+      '';
+  };
+
+}