Allow extensions to have external dependencies (#1018)

Signed-off-by: Jari Kolehmainen <jari.kolehmainen@gmail.com>

extensions/example-extension/tsconfig.json

@@ -1,13 +1,25 @@
 {
-  "extends": "../../tsconfig.json",
   "compilerOptions": {
-    "outDir": ".",
+    "outDir": "dist",
     "module": "CommonJS",
+    "target": "ES2017",
+    "lib": ["ESNext", "DOM", "DOM.Iterable"],
+    "moduleResolution": "Node",
     "sourceMap": false,
-    "declaration": false
+    "declaration": false,
+    "strict": false,
+    "noImplicitAny": true,
+    "skipLibCheck": true,
+    "esModuleInterop": true,
+    "allowSyntheticDefaultImports": true,
+    "jsx": "react"
   },
   "include": [
     "../../types",
-    "./example-extension.tsx"
+    "./index.tsx"
+  ],
+  "exclude": [
+    "node_modules",
+    "*.js"
   ]
 }