Fix readme link (#170)

* fix readme link

* fix readme link

README.md

@@ -58,10 +58,10 @@ pip install paddleslim -i https://pypi.org/simple
 
 ## Usage
 
-- [QuickStart](docs/zh_cn/quick_start): Introduce how to use PaddleSlim by simple examples.
-- [Advanced Tutorials](docs/zh_cn/tutorials)：Tutorials about advanced usage of PaddleSlim.
-- [Model Zoo](docs/zh_cn/model_zoo.md)：Benchmark and pretrained models.
-- [API Documents](https://paddlepaddle.github.io/PaddleSlim/api_cn/index.html)
+- [QuickStart](https://paddlepaddle.github.io/PaddleSlim/quick_start/index_en.html): Introduce how to use PaddleSlim by simple examples.
+- [Advanced Tutorials](https://paddlepaddle.github.io/PaddleSlim/tutorials/index_en.html)：Tutorials about advanced usage of PaddleSlim.
+- [Model Zoo](https://paddlepaddle.github.io/PaddleSlim/model_zoo_en.html)：Benchmark and pretrained models.
+- [API Documents](https://paddlepaddle.github.io/PaddleSlim/api_en/index_en.html)
 - [PaddleDetection](https://github.com/PaddlePaddle/PaddleDetection/tree/master/slim): Introduce how to use PaddleSlim in PaddleDetection library.
 - [PaddleSeg](https://github.com/PaddlePaddle/PaddleSeg/tree/develop/slim): Introduce how to use PaddleSlim in PaddleSeg library.
 - [PaddleLite](https://paddlepaddle.github.io/Paddle-Lite/): How to use PaddleLite to deploy models generated by PaddleSlim.