Update README.md

Author: z-song

README.md

@@ -1,6 +1,8 @@
 Several c-lick language editor extensions for laravel-admin based on code-mirror
 ======
 
+[DEMO](http://demo.laravel-admin.org/code-mirror/clike) (Login using `admin/admin`)
+
 ## Installation 
 
 ```bash
@@ -64,4 +66,4 @@ $form->clang('code')->height(500);
 
 License
 ------------
-Licensed under [The MIT License (MIT)](LICENSE).
+Licensed under [The MIT License (MIT)](LICENSE).