Merge pull request #4303 from wzgliang/develop

[ISSUE #4289] Add some detail descriptions to README

Author: caigy

README.md

@@ -50,6 +50,7 @@ It offers a variety of features:
 * [RocketMQ Incubating Community Projects](https://github.com/apache/rocketmq-externals): Apache rocketmq is incubating the ecological project warehouse, including Spark, ES, Beats and other connectors.
 * [rocketmq-site](https://github.com/apache/rocketmq-site)
 
+
 ----------
 ## Learn it & Contact us
 * Mailing Lists: <https://rocketmq.apache.org/about/contact/>