feat(demo): add landing page with docs (#1951)

docs/tsconfig.app.json

@@ -0,0 +1,27 @@
+{
+  "extends": "../tsconfig.json",
+  "compilerOptions": {
+    "sourceMap": true,
+    "declaration": false,
+    "moduleResolution": "node",
+    "emitDecoratorMetadata": true,
+    "experimentalDecorators": true,
+    "lib": [
+      "es2017",
+      "dom"
+    ],
+    "outDir": "../out-tsc/app",
+    "module": "es2015",
+    "baseUrl": ".",
+    "types": []
+  },
+  "exclude": [
+    "test.ts",
+    "**/*.spec.ts",
+    "assets/**/*.ts",
+    "dist/**/*"
+  ],
+  "include": [
+    "../docs/**/*"
+  ]
+}