Add docs for configuration command (#501)

* Add confiugration command

* format

* rephrase

Author: Kangaxx-0

book/configuration.md

@@ -51,6 +51,17 @@ These are some important variables to look at for Nushell-specific settings:
 - `PROMPT_INDICATOR_VI_NORMAL = "〉 "`
 - `PROMPT_MULTILINE_INDICATOR = "::: "`
 
+### Configurations with built-in commands
+
+Starting with release v0.64 of Nushell, we have introduced two new commands(`config nu` and `config env`) which help you quickly edit nu configurations with your preferred text editor/IDE
+
+Nushell follows underneath orders to locate the editor:
+
+1. `$config.buffer_editor`
+2. `$env.EDITOR`
+3. `$env.VISUAL`
+4. If 1~3 not found, then launch `notepad` for windows, otherwise run `nano`
+
 ### Color Config section
 
 You can learn more about setting up colors and theming in the [associated chapter](coloring_and_theming.md).

zh-CN/book/configuration.md

@@ -51,6 +51,17 @@ _(尽管 `$env.config` 是一个环境变量，按照惯例它仍然在 `config.
 - `PROMPT_INDICATOR_VI_NORMAL = "〉 "`
 - `PROMPT_MULTILINE_INDICATOR = "::: "`
 
+### 使用内置命令
+
+从 Nushell 0.64 版本开始新增了 2 个内置命令(`config nu` 和 `config env`),凭借这两个命令，你可以使用自定义的编辑器或者 IDE 快速地更改 Nushell 配置信息
+
+Nushell 遵循如下的规则来匹配编辑器:
+
+1. `$config.buffer_editor`
+2. `$env.EDITOR`
+3. `$env.VISUAL`
+4. 如果上面都未匹配成功，则针对 Windows 运行`notepad`, 其他系统`nano`
+
 ### 颜色配置部分
 
 你可以在 [相关章节](coloring_and_theming.md) 中了解更多关于设置颜色和主题的信息。