Added JS engine.

tsconfig.json

@@ -0,0 +1,23 @@
+{
+  "compilerOptions": {
+    "target": "ES3",
+    "lib": [ "esnext" ],
+    "allowJs": true,
+    "skipLibCheck": true,
+    "strict": true,
+    "forceConsistentCasingInFileNames": true,
+    "esModuleInterop": true,
+    "module": "esnext",
+    "jsx": "preserve",
+    "baseUrl": ".",
+    "outDir": "build/assets/scripts",
+    "alwaysStrict": false,
+    "noImplicitUseStrict": true
+  },
+  "exclude": [
+    "node_modules"
+  ],
+  "include": [
+    "**/*.ts", "**/*.tsx", "**/*.d.ts"
+  ]
+}