Updated API Gateway tips

Added note about support of binary data.

README.md

@@ -1,4 +1,4 @@
-![An Open Guide](figures/signpost-horiz1-1600.jpg)
+![An Open Guide](figures/signpost-horiz1-1600.jpg)
 
 The Open Guide to Amazon Web Services
 =====================================
@@ -45,7 +45,7 @@ Table of Contents
 | [DynamoDB](#dynamodb) | [📗](#dynamodb-basics) | [📘](#dynamodb-tips) | [📙](#dynamodb-gotchas-and-limitations) |
 | [ECS](#ecs) | [📗](#ecs-basics) | [📘](#ecs-tips) |  |
 | [Lambda](#lambda) | [📗](#lambda-basics) | [📘](#lambda-tips) | [📙](#lambda-gotchas-and-limitations) |
-| [API Gateway](#api-gateway) | [📗](#api-gateway-basics) |  | [📙](#api-gateway-gotchas-and-limitations) |
+| [API Gateway](#api-gateway) | [📗](#api-gateway-basics) | [📘](#api-gateway-tips) | [📙](#api-gateway-gotchas-and-limitations) |
 | [Route 53](#route-53) | [📗](#route-53-basics) | [📘](#route-53-tips) |  |
 | [CloudFormation](#cloudformation) | [📗](#cloudformation-basics) | [📘](#cloudformation-tips) | [📙](#cloudformation-gotchas-and-limitations) |
 | [VPCs, Network Security, and Security Groups](#vpcs-network-security-and-security-groups) | [📗](#vpc-basics) | [📘](#vpc-and-network-security-tips) | [📙](#vpc-and-network-security-gotchas-and-limitations) |
@@ -1263,6 +1263,10 @@ API Gateway
 - [Kong](https://getkong.org) is an open-source, on-premises API and microservices gateway built on nginx with Lua. Kong is extensible through “plugins”.
 - [Tyk](https://tyk.io) is an open-source API gateway implemented in Go and available in the cloud, on-premises or hybrid.
 
+### API Gateway Tips
+
+-	🔹Prior to 2016-11, you could only send and receive plain text data (so people would base64-encode binary data), but binary data is [now](https://aws.amazon.com/about-aws/whats-new/2016/11/binary-data-now-supported-by-api-gateway/) supported.
+
 ### API Gateway Gotchas and Limitations
 
 -	🔸API Gateway only supports encrypted (https) endpoints, and does not support unencrypted HTTP. (This is probably a good thing.)