更新readme，添加--share说明。

README.md

@@ -162,6 +162,7 @@ In the following table, we list all advanced options for reference:
 | `-t`  | [Multi-threads](#threads) | `pdf2zh example.pdf -t 1` |
 | `-o`  | Output dir | `pdf2zh example.pdf -o output` |
 | `-f`, `-c` | [Exceptions](#exceptions) | `pdf2zh example.pdf -f "(MS.*)"` |
+| `--share` | get gradio public link | `pdf2zh -i --share` |
 
 <h3 id="partial">Full / partial document translation</h3>
 

README_zh-CN.md

@@ -162,6 +162,7 @@
 | `-t`  | [多线程](#threads) | `pdf2zh example.pdf -t 1` |
 | `-o`  | 输出目录 | `pdf2zh example.pdf -o output` |
 | `-f`, `-c` | [例外规则](#exceptions) | `pdf2zh example.pdf -f "(MS.*)"` |
+| `--share` | 获取gradio公开链接 | `pdf2zh -i --share` |
 
 <h3 id="partial">全文或部分文档翻译</h3>