Create README.md

+# react-native-lewin-qrcode
+react-native 识别照片二维码
+
+## Table of contents
+- [Install](#install)
+- [Usage](#usage)
+
+## Install
+### 1: 暂时没有发布到npm所以需要自己手动添加到dependencies 
+`"react-native-lewin-qrcode": "git://github.com/LewinJun/react-native-lewin-qrcode.git#1.0"`
+### 2: yarn install 或 npm install
+### 3: react-native link react-native-lewin-qrcode
+
+## Usage
+```javascript
+import {readerQR} from 'react-native-lewin-qrcode'
+  //path 图片文件的路径
+  readerQR(path).then((data)=>{
+     Alert.alert('识别结果',data);
+  }).catch((err)=>{
+     Alert.alert('识别失败');
+  });
+```javascript