Update README.md

python/examples/fit_a_line/README.md

 # Fit a line example, prediction through rpc service
-Start rpc service
+
+([简体中文](./README_CN.md)|English)
+
+## Start rpc service
 ``` shell
 sh get_data.sh
 python test_server.py uci_housing_model/
 ```
 
-Prediction
+## Prediction
 ``` shell
 python test_client.py uci_housing_client/serving_client_conf.prototxt
 ```
 
-# prediction through http service
+## prediction through http service
 Start a web service with default web service hosting modules
 ``` shell
 python -m paddle_serving_server.web_serve --model uci_housing_model/ --thread 10 --name uci --port 9393 --name uci
 ```
 
-Prediction through http post
+## Prediction through http post
 ``` shell
 curl -H "Content-Type:application/json" -X POST -d '{"x": [0.0137, -0.1136, 0.2553, -0.0692, 0.0582, -0.0727, -0.1583, -0.0584, 0.6283, 0.4919, 0.1856, 0.0795, -0.0332], "fetch":["price"]}' http://127.0.0.1:9393/uci/prediction
 ```