Update doc, add jetbrains credits.

Author: agreatfool

README.md

@@ -14,6 +14,7 @@ grpc_tools_node_protoc_ts
 * [About vulnerability](#about-vulnerability)
 * [About Docker](#about-docker)
 * [Environment](#environment)
+* [Credits](#credits)
 
 ## Aim
 Generate corresponding TypeScript d.ts codes according to js codes generated by [grpc_tools_node_protoc](https://www.npmjs.com/package/grpc-tools).
@@ -639,3 +640,8 @@ npm list -g --depth=0 | grep grpc-tools
 tsc --version
 # Version 3.7.3
 ```
+
+## Credits
+<a href="https://www.jetbrains.com/?from=grpc_tools_node_protoc_ts">
+    <img src="doc/images/jetbrains.png" width="100px" height="100px">
+</a>