update readme

Author: horike37

README.md

@@ -1,2 +1,12 @@
 # Serverless Apigateway Service proxy
 The Serverless Framewrok plugin to support AWS service proxy integration of API Gateway
+
+## How to use
+Define something to setting of AWS services you want to integrate with under `custom > apiGatewayServiceProxy`
+
+### Kinesis
+```yaml
+custom:
+  apiGatewayServiceProxy:
+    path: /kinesis/{streamname}
+```