fix README.md (#40)

README.md

@@ -116,10 +116,11 @@ They are defined as constant in root package with prefix `Tag`.
 
 ## Plugins
 
-Plugins is integrated with specific framework, for instance, `net/http`, `gRPC`, `mysql` and etc. They
+Plugins is integrated with specific framework, for instance, `net/http`, `gin` and etc. They
 are stored in `plugins` package.
 
  1. [HTTP client/server example](plugins/http/example_http_test.go)
+ 1. [gin example](plugins/gin/example_gin_test.go)
 
 # License
 Apache License 2.0. See [LICENSE](LICENSE) file for details.