feat(composer): add library skeleton

re orchestratora/rfcs#2

angular.json

@@ -293,6 +293,48 @@
       },
       "tags": ["e2e", "ui", "web"],
       "implicitDependencies": ["ui-web-example"]
+    },
+    "composer": {
+      "root": "libs/composer",
+      "sourceRoot": "libs/composer/src",
+      "projectType": "library",
+      "prefix": "orc",
+      "architect": {
+        "build": {
+          "builder": "@nrwl/angular:package",
+          "outputs": ["dist/libs/composer"],
+          "options": {
+            "project": "libs/composer/ng-package.json"
+          },
+          "configurations": {
+            "production": {
+              "tsConfig": "libs/composer/tsconfig.lib.prod.json"
+            },
+            "development": {
+              "tsConfig": "libs/composer/tsconfig.lib.json"
+            }
+          },
+          "defaultConfiguration": "production"
+        },
+        "test": {
+          "builder": "@nrwl/jest:jest",
+          "outputs": ["coverage/libs/composer"],
+          "options": {
+            "jestConfig": "libs/composer/jest.config.js",
+            "passWithNoTests": true
+          }
+        },
+        "lint": {
+          "builder": "@nrwl/linter:eslint",
+          "options": {
+            "lintFilePatterns": [
+              "libs/composer/src/**/*.ts",
+              "libs/composer/src/**/*.html"
+            ]
+          }
+        }
+      },
+      "tags": ["utility", "ui"]
     }
   }
 }

libs/composer/.eslintrc.json

@@ -0,0 +1,36 @@
+{
+  "extends": ["../../.eslintrc.json"],
+  "ignorePatterns": ["!**/*"],
+  "overrides": [
+    {
+      "files": ["*.ts"],
+      "extends": [
+        "plugin:@nrwl/nx/angular",
+        "plugin:@angular-eslint/template/process-inline-templates"
+      ],
+      "rules": {
+        "@angular-eslint/directive-selector": [
+          "error",
+          {
+            "type": "attribute",
+            "prefix": "orc",
+            "style": "camelCase"
+          }
+        ],
+        "@angular-eslint/component-selector": [
+          "error",
+          {
+            "type": "element",
+            "prefix": "orc",
+            "style": "kebab-case"
+          }
+        ]
+      }
+    },
+    {
+      "files": ["*.html"],
+      "extends": ["plugin:@nrwl/nx/angular-template"],
+      "rules": {}
+    }
+  ]
+}

libs/composer/README.md

@@ -0,0 +1,24 @@
+# @orchestrator/composer
+
+> Allows to visually create and validate JSON UIs for Orchestrator.
+
+![@orchestrator/composer](https://img.shields.io/npm/v/@orchestrator/composer)
+
+## Registration
+
+```ts
+import { NgModule } from '@angular/core';
+import { OrchestratorCoreModule } from '@orchestrator/core';
+import { ComposerModule } from '@orchestrator/composer';
+
+@NgModule({
+  imports: [OrchestratorCoreModule.forRoot(), ComposerModule.forRoot()],
+})
+export class AppModule {}
+```
+
+## Components list
+
+| Component | Description |
+| --------- | ----------- |
+|           |             |