增加Excel导入导出示例功能

server/model/request/exa_file_upload_and_download.go

@@ -0,0 +1,8 @@
+package request
+
+import "gin-vue-admin/model"
+
+type ExcelInfo struct {
+	FileName string `json:"fileName"`
+	InfoList []model.SysBaseMenu `json:"infoList"`
+}