Modify readme contents (#18470)

* Adding communication part in readme, test=develop

* modify_readme_contents,test=develop

* Update README_cn.md

README.md

@@ -32,6 +32,7 @@ pip install paddlepaddle-gpu==1.5.0.post87
 
 # For installation on other platform, refer to http://paddlepaddle.org/
 ```
+Now our developers could acquire Tesla V100 online computing resources for free. If you create a program by AI Studio, you would obtain 12 hours to train models online per day. If you could insist on that for five consecutive days, then you would own extra 48 hours. [Click here to start](http://ai.baidu.com/support/news?action=detail&id=981).
 
 ## Features
 

README_cn.md

@@ -30,6 +30,7 @@ pip install paddlepaddle-gpu==1.5.0.post87
 
 # 其他平台上的安装指引请参考 http://paddlepaddle.org/
 ```
+PaddlePaddle用户可领取**免费Tesla V100在线算力资源**，训练模型更高效。**每日登陆即送12小时**，**连续五天运行再加送48小时**，[前往使用免费算力](https://ai.baidu.com/support/news?action=detail&id=981)。
 
 ## 特性