docs(example): add CORS + DefaultAuthorizer example

Author: adanilev

examples/2016-10-31/api_lambda_auth_cors/README.md

@@ -0,0 +1,26 @@
+# api_lambda_auth_cors
+
+## About
+
+This example shows how to configure a TOKEN Lambda Authorizer as the `DefaultAuthorizer` for an API with CORS enabled.
+
+## Installation
+
+1. Provide a bucket name and deploy the resources
+    ```bash 
+    S3_BUCKET_NAME=your-bucket-name-here \ 
+    npm run package-deploy
+    ```
+1. Install the required NPM dependencies
+    ```bash
+    npm install
+    ```
+1. Start the web server
+    ```bash
+    npm run start
+    ```
+1. Open `http://localhost:8080` in a browser, click the button and an alert will appear with the lambda response
+
+## Cleanup
+
+1. `aws cloudformation delete-stack --stack-name authorizer-cors-example`