add known user

README.md

@@ -139,3 +139,4 @@ The project is licensed under the [Apache 2 license](https://github.com/ctripcor
 ![头等仓](https://github.com/ctripcorp/apollo/blob/master/doc/images/known-users/toodc.png) 
 ![吉祥航空](https://github.com/ctripcorp/apollo/blob/master/doc/images/known-users/juneyaoair.png) 
 ![263移动通信](https://github.com/ctripcorp/apollo/blob/master/doc/images/known-users/263mobile.png) 
+![投投金融](https://github.com/ctripcorp/apollo/blob/master/doc/images/known-users/toutoujinrong.png)