format README and README_zh txt

README.md

@@ -8,7 +8,8 @@ use [zt-zip](<https://github.com/zeroturnaround/zt-zip>) for unzip xapk,thanks
 
 [中文说明](./README_zh.md)
 
-###update
+### update ###
+
 Because Meizu and vivo have modified the system installation-related classes,xapk(split apk) cannot be successfully installed, so check it and do nothing if os is flyme or funtouch os.
 
 In addition, please refer to the article：https://www.jianshu.com/p/580b61ee7aee

README_zh.md

@@ -6,7 +6,8 @@
 
 使用 [zt-zip](<https://github.com/zeroturnaround/zt-zip>) 来解压xapk,感谢
 
-###更新
+### 更新 ###
+
 因为魅族和vivo对系统安装相关的类进行了修改，导致split apk的xapk无法安装成功，故进行检查，如果是flyme或者funtouch os则不做处理。
 
 另外可以参考文章：https://www.jianshu.com/p/580b61ee7aee