Update README.md

README.md

-<img src='https://paddle-serving.bj.bcebos.com/imdb-demo%2FLogoMakr-3Bd2NM-300dpi.png' width = "600" height = "127">
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+<img src='https://paddle-serving.bj.bcebos.com/imdb-demo%2FLogoMakr-3Bd2NM-300dpi.png' width = "400" height = "81">
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 [![Release](https://img.shields.io/badge/Release-0.0.3-yellowgreen)](Release)
 [![Issues](https://img.shields.io/github/issues/PaddlePaddle/Serving)](Issues)
 [![License](https://img.shields.io/github/license/PaddlePaddle/Serving)](LICENSE)
 [![Slack](https://img.shields.io/badge/Join-Slack-green)](https://paddleserving.slack.com/archives/CU0PB4K35)
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+<p>
 
 [中文](https://github.com/PaddlePaddle/Serving/blob/develop/README_CN.md)