update doc

Author: noogen

README.md

@@ -116,6 +116,6 @@ And if that doesn't work, you can always use your custom nginx config by passing
 
 # Point of Interest
 * [images.weserv.nl](https://github.com/weserv/images) is another great project to look at if you need additional features with image resizing.  The original purpose of this library (nginx-image-proxy) is to provide high performance and low resource utilization image private microservice.  We searched high and low but did not find a good solution.  At that time, we saw great potential with images.weserv.nl, but was held back because it was using php.  Since July 2018, it was rewritten with lua and direct c binding; as a result, it has became the next best solution and continue to improve.  The authors also generiously provide free endpoint for public use.  This help prove their implementation to be well battle-tested for use in any production environment.
-> Update, as of September 2019, images.weserv.nl was rewritten again as C++ so it has now became the better/best choice.
+> Update, as of September 2019, images.weserv.nl was rewritten again as C++ so it has now became the better/best choice.  We are now sun-setting this project, only maintenance and security support - no new feature, for the future date of December 2021 or 2 years from December 2020.
 
 # MIT