update README. Add a description about showLength

Author: leezng

README.md

@@ -54,7 +54,8 @@ export default {
 | Attribute | Level | Description | Type | Default |
 |-------- |-------- |-------- |-------- | -------- |
 | data | basic | json data | JSON object | - |
-| deep | basic |data depth, data larger than this depth will not be expanded | number | Infinity |
+| deep | basic | data depth, data larger than this depth will not be expanded | number | Infinity |
+| showLength | basic | whether to show the length when closed | boolean | false |
 | path | advanced | root data path | string | root |
 | pathChecked | advanced | defines the selected data path | array | [] |
 | pathSelectable | advanced | defines whether a data path supports selection | Function(itemPath, itemData) | - |

README.zh-CN.md

@@ -55,6 +55,7 @@ export default {
 |-------- |-------- |-------- |-------- | -------- |
 | data | 基础 | 待美化的源数据，注意不是 `JSON` 字符串 | `JSON` 对象 | - |
 | deep | 基础 | 数据深度, 大于该深度的数据将不被展开 | number | Infinity |
+| showLength | 基础 | 是否在数据线闭合的时候展示长度 | boolean | false |
 | path | 高级 | 定义最顶层数据层级 | string | root |
 | pathChecked | 高级 | 定义哪些数据层级是已被选中的 | array | [] |
 | pathSelectable | 高级 | 定义哪些数据层级是可以被选中的 | Function(itemPath, itemData) | - |