v2 readme

Author: 李卓原

README.md

@@ -15,8 +15,8 @@
 [Update log](https://github.com/OpenFlutter/flutter_screenutil/blob/master/CHANGELOG.md)
 
 ## Note
-[v3](https://github.com/OpenFlutter/flutter_screenutil/tree/beta) requires `flutter >= 1.19.0`.  
-[v2](https://github.com/OpenFlutter/flutter_screenutil) requires `flutter < 1.19.0`.  
+[v3](https://github.com/OpenFlutter/flutter_screenutil/tree/beta) requires `flutter >= 1.19.0`.
+[v2](https://github.com/OpenFlutter/flutter_screenutil) support all versions.
 
 ## Usage:
 

README_CN.md

@@ -19,7 +19,7 @@
 [更新日志](https://github.com/OpenFlutter/flutter_screenutil/blob/master/CHANGELOG.md)
 
 ## Note
-[v3](https://github.com/OpenFlutter/flutter_screenutil/tree/beta)可用于`flutter >= 1.19.0`  
+[v3](https://github.com/OpenFlutter/flutter_screenutil/tree/beta)可用于`flutter >= 1.19.0`.    
 [v2](https://github.com/OpenFlutter/flutter_screenutil)可用于`flutter > 1.19.0`。
 
 ## 使用方法:

README_PT.md

@@ -16,7 +16,7 @@
 
 ## Note
 [v3](https://github.com/OpenFlutter/flutter_screenutil/tree/beta) requer `flutter >= 1.19.0`.
-[v2](https://github.com/OpenFlutter/flutter_screenutil) requer `flutter < 1.19.0`.
+[v2](https://github.com/OpenFlutter/flutter_screenutil) support all versions.
 
 ## Como usar: