remove rabbitmq and kafka

- already listed at https://landscape.cncf.io/?group=projects-and-products&view-mode=card#app-definition-and-development--streaming-messaging
- add link to CNCF.io/Streaming and Messaging category

README.md

@@ -579,12 +579,12 @@ Web-based project management and bug tracking systems.
 
 [Message queues](https://en.wikipedia.org/wiki/Message_queue) and [message broker](https://en.wikipedia.org/wiki/Message_broker) software, typically used for inter-process communication (IPC), or for inter-thread communication within the same process.
 
+_See also: [Cloud Native Landscape - Streaming & Messaging](https://landscape.cncf.io/?group=projects-and-products&view-mode=card#app-definition-and-development--streaming-messaging)_
+
 - [ActiveMQ](https://activemq.apache.org/) - Java message broker. ([Source Code](https://github.com/apache/activemq)) `Apache-2.0` `Java`
 - [BeanstalkD](https://beanstalkd.github.io/) - A simple, fast work queue. ([Source Code](https://github.com/beanstalkd/beanstalkd)) `MIT` `C`
 - [Gearman](http://gearman.org/) - Fast multi-language queuing/job processing platform. ([Source Code](https://github.com/gearman/gearmand)) `BSD-3-Clause` `C++`
-- [Kafka](https://kafka.apache.org) - Extremely high performance publish/subscribe message system. ([Source Code](https://github.com/apache/kafka)) `Apache-2.0` `Java`
 - [NSQ](https://nsq.io/) - A realtime distributed messaging platform. ([Source Code](https://github.com/nsqio/nsq)) `MPL-2.0` `Go`
-- [RabbitMQ](https://www.rabbitmq.com/) - Robust, fully featured, cross distro queuing system. ([Source Code](https://github.com/rabbitmq/rabbitmq-server)) `MPL-2.0/Apache-2.0` `Erlang`
 - [ZeroMQ](https://zeromq.org/) - Lightweight queuing system. ([Source Code](https://github.com/zeromq)) `GPL-3.0` `C++`