Initial refactoring for kubenix 2.0

Implemented features:

- Improved and reimplemented submodule system, independent of
kubernetes module definitions
- Pre-generated kubernetes module definitions with explicit API
versioning support

release.nix

@@ -0,0 +1,147 @@
+{pkgs ? import <nixpkgs> {}}:
+
+let
+  generate = path: import ./k8s/generator.nix {
+    inherit pkgs;
+    inherit (pkgs) lib;
+    inherit path;
+  };
+
+  kubenix = import ./. { inherit pkgs; };
+in {
+  generate = pkgs.linkFarm "k8s-generated.nix" [{
+    name = "v1.7.nix";
+    path = generate ./k8s/specs/1.7/swagger.json;
+  } {
+    name = "v1.8.nix";
+    path = generate ./k8s/specs/1.8/swagger.json;
+  } {
+    name = "v1.9.nix";
+    path = generate ./k8s/specs/1.9/swagger.json;
+  } {
+    name = "v1.10.nix";
+    path = generate ./k8s/specs/1.10/swagger.json;
+  }];
+
+  test = kubenix.buildResources ({lib, config, kubenix, ...}: with lib; {
+    imports = [
+      kubenix.k8s
+      kubenix.submodules
+    ];
+
+    config = {
+      kubernetes.version = "1.10";
+
+      kubernetes.api.defaults.all.metadata.namespace = mkDefault "my-namespace";
+
+      submodules.defaults = {config, parentConfig, ...}: {
+        kubernetes = mkIf (hasAttr "kubernetes" config) {
+          version = mkDefault parentConfig.kubernetes.version;
+          api.defaults = mkDefault parentConfig.kubernetes.api.defaults;
+        };
+      };
+
+      submodules.imports = [
+        # import nginx submodule
+        ./examples/module/nginx.nix
+
+        # import of patched nginx submodule
+        {
+          modules = [./examples/module/nginx.nix ({config, ...}: {
+            config = {
+              submodule.version = mkForce "1.0-xtruder";
+              args.image = "xtruder/nginx";
+
+              submodules.instances.test2 = {
+                submodule = "test";
+              };
+
+              kubernetes.objects = config.submodules.instances.test2.config.kubernetes.objects;
+            };
+          })];
+        }
+
+        # definition of test submodule
+        {
+          module = {submodule, ...}: {
+            submodule.name = "test";
+
+            imports = [
+              kubenix.k8s
+            ];
+
+            kubernetes.api.Pod.my-pod = {
+              metadata.name = submodule.name;
+            };
+          };
+        }
+      ];
+
+      submodules.instances.nginx-default = {
+        submodule = "nginx";
+      };
+
+      submodules.instances.nginx-xtruder = {
+        submodule = "nginx";
+        version = "1.0-xtruder";
+
+        config = {
+          args.replicas = 9;
+          kubernetes.api.Deployment.nginx.metadata.namespace = "other-namespace";
+        };
+      };
+
+      submodules.instances.test = {
+        submodule = "test";
+      };
+
+      #kubernetes.api."cloud.google.com".v1beta1.BackendConfig.my-backend = {
+      #};
+
+      #modules.nginx1 = {
+        #args = {
+          #replicas = 2;
+        #};
+
+        #kubernetes.api.defaults.deployments = {
+          #spec.replicas = mkForce 3;
+        #};
+
+        #kubernetes.customResources = [{
+          #group = "cloud.google.com";
+          #version = "v1beta1";
+          #kind = "BackendConfig";
+          #plural = "backendconfigs";
+          #description = "Custom resource";
+          #module = {
+            #options.spec = {
+              #cdn = mkOption {
+                #description = "My cdn";
+                #type = types.str;
+                #default = "test";
+              #};
+            #};
+          #};
+        #}];
+      #};
+
+      #modules.nginx2 = {
+        #args = {
+          #replicas = 2;
+        #};
+
+        #kubernetes.api.defaults.deployments = {
+          #spec.replicas = mkForce 3;
+        #};
+      #};
+
+      kubernetes.objects = mkMerge [
+        config.submodules.instances.nginx-default.config.kubernetes.objects
+        config.submodules.instances.nginx-xtruder.config.kubernetes.objects
+        config.submodules.instances.test.config.kubernetes.objects
+      ];
+
+      #kubernetes.customResources = config.modules.nginx1.kubernetes.customResources;
+    };
+  });
+}