Add componentDidCatch example

examples/.babelrc

 {
-  "babelrc": false
-}
\ No newline at end of file
+  "presets": ["../babel"]
+}

examples/with-componentdidcatch/package.json

+{
+  "name": "hello-world",
+  "version": "1.0.0",
+  "scripts": {
+    "dev": "next",
+    "build": "next build",
+    "start": "next start"
+  },
+  "dependencies": {
+    "next": "6.0.0-canary.6",
+    "react": "^16.0.0",
+    "react-dom": "^16.0.0"
+  },
+  "license": "ISC"
+}

examples/with-componentdidcatch/pages/_app.js

+import App from 'next/app'
+
+export default class MyApp extends App {
+  componentDidCatch (error, errorInfo) {
+    console.log('CUSTOM ERROR HANDLING', error)
+    // This is needed to render errors correctly in development / production
+    super.componentDidCatch(error, errorInfo)
+  }
+}

examples/with-componentdidcatch/pages/index.js

+export default () => {
+  // Render time error
+  throw new Error('Test')
+}