add README for java client

java/README.md

+## Java Demo
+
+### Install package
+```
+mvn compile
+mvn install
+cd examples
+mvn compile
+mvn install
+```
+
+### Start Server
+
+take the fit_a_line demo as example
+
+```
+ python -m paddle_serving_server.serve --model uci_housing_model --thread 10 --port 9393 --use_multilang #CPU
+python -m paddle_serving_server_gpu.serve --model uci_housing_model --thread 10 --port 9393 --use_multilang #GPU
+```
+
+### Client Predict
+```
+java -cp paddle-serving-sdk-java-examples-0.0.1-jar-with-dependencies.jar PaddleServingClientExample fit_a_line
+```

java/README_CN.md

+## Java 示例
+
+### 安装客户端依赖
+```
+mvn compile
+mvn install
+cd examples
+mvn compile
+mvn install
+```
+
+### 启动服务端
+
+以fit_a_line模型为例
+
+```
+ python -m paddle_serving_server.serve --model uci_housing_model --thread 10 --port 9393 --use_multilang #CPU
+python -m paddle_serving_server_gpu.serve --model uci_housing_model --thread 10 --port 9393 --use_multilang #GPU
+```
+
+### 客户端预测
+```
+java -cp paddle-serving-sdk-java-examples-0.0.1-jar-with-dependencies.jar PaddleServingClientExample fit_a_line
+```