doc: update bufferFactory.create()

Signed-off-by: imnemo <291400733@qq.com>

README-zh.md

@@ -13,4 +13,32 @@
 # Buffer Factory - ([README in English](./README.md))
 `node-factory`封装了`new Buffer(args...)`和Buffer.from(args...)，使得创建一个Buffer对象时，不必考虑Node版本问题，避免出错，也可使代码更好的向下兼容。
 
-本模块有较充分的单元测试和完善的使用文档。
+本模块有较充分的单元测试和完善的使用文档。
+
+# 使用
+
+## 安装
+
+`npm i buffer-factory`
+
+## 调用
+
+```javascript
+const bufferFactory = require('buffer-factory')
+bufferFactory.create('2b', 'hex');
+
+// 已废弃
+bufferFactory('2b', 'hex');
+```
+
+## 实现原理
+
+`Buffer.from` is preffered to be used when it's accessible.
+
+`Buffer.from` is added from v5.10.0, as the api document shows. But some node version, v4.2.6 for example, `Buffer.from` is a function, however, there is an error when you call `Buffer.from(string, encoding)`(error like `hex is not function`). So I also take the node version into account.  
+
+For low versions of Node.js, this module use `new Buffer(...)`.  
+
+You're free to pass in the same params as `Buffer.from(...)` and `new Buffer(...)`, I will handle the rest for you.  
+
+You're also free to check `index.js` for the implementation code :).

README.md

@@ -25,7 +25,10 @@ This module has been well unit tested and documented.
 
 ```javascript
 const bufferFactory = require('buffer-factory')
-bufferFactory('2b', 'hex')
+bufferFactory.create('2b', 'hex');
+
+// deprecated
+bufferFactory('2b', 'hex');
 ```
 
 ## Implementation

package.json

@@ -1,6 +1,6 @@
 {
   "name": "buffer-factory",
-  "version": "1.0.8",
+  "version": "1.0.9",
   "description": "Make it no pain to create a Buffer object by encapsulate Buffer.from an new Buffer().",
   "main": "index.js",
   "scripts": {