feat:add GetExeDllVersion for fileutil,random,package (#257)

* 增加GetExeDllVersion函数获取exe,dll版本号

* 多打文字

* 定位忘记...

* 单独剥离出来一个为windows的,增加RandNumLen为取指定长度随机数.

* ....

* 增加test测试

docs/api/packages/fileutil.md

@@ -52,7 +52,7 @@ import (
 -   [ReadFile](#ReadFile)
 -   [ChunkRead](#ChunkRead)
 -   [ParallelChunkRead](#ParallelChunkRead)
-
+-   [GetVersion](#Version)
 <div STYLE="page-break-after: always;"></div>
 
 ## 文档
@@ -1076,4 +1076,34 @@ func main() {
     // Jim,21,male
     // 2
 }
+```
+### <span id="Version">GetExeDllVersion</span>
+
+<p>返回exe,dll文件版本号(仅Window平台).</p>
+
+<b>函数签名:</b>
+
+```go
+func GetExeDllVersion(filePath string) (string, error)
+```
+
+<b>示例:<span style="float:right;display:inline-block;">[运行](https://go.dev/play/p/s_Tl7lZoAaY)</span></b>
+
+```go
+package main
+
+import (
+    "fmt"
+    "github.com/duke-git/lancet/v2/fileutil"
+)
+
+func main() {
+    v, err := fileutil.GetExeDllVersion(`C:\Program Files\Tencent\WeChat\WeChat.exe`)
+	if err != nil {
+		panic(err)
+    }
+    fmt.Println(v)
+    // Output:
+    // 3.9.10.19
+}
 ```

docs/api/packages/random.md

@@ -40,6 +40,7 @@ import (
 -   [RandStringSlice](#RandStringSlice)
 -   [RandBool](#RandBool)
 -   [RandBoolSlice](#RandBoolSlice)
+-   [RandNumLen](#RandNumLen)
 
 
 <div STYLE="page-break-after: always;"></div>
@@ -522,4 +523,29 @@ func main() {
     result := random.RandBoolSlice(2)
     fmt.Println(result) // [true false] (random)
 }
+```
+### <span id="RandNumLen">RandNumLen</span>
+
+<p>生成指定长度的随机数</p>
+
+<b>函数签名:</b>
+
+```go
+func RandNumLen(len int) int
+```
+
+<b>实例:<span style="float:right;display:inline-block;">[运行](https://go.dev/play/p/o-VSjPjnILI)</span></b>
+
+```go
+package main
+
+import (
+    "fmt"
+    "github.com/duke-git/lancet/v2/random"
+)
+
+func main() {
+    i := random.RandNumLen(2)
+    fmt.Println(i)
+}
 ```