add laravel version req to rdme

ctf0 · ctf0 · commit a80c8a9ab3a7 · 2017-08-28T10:09:40.000+02:00
diff --git a/README.md b/README.md
@@ -20,6 +20,8 @@
 
 - to optimize uploaded files on the fly try [approached](https://github.com/approached/laravel-image-optimizer) or [spatie](https://github.com/spatie/laravel-image-optimizer)
 
+- package requires Laravel v5.4+
+
 ## Installation
 
 - `composer require ctf0/media-manager`
