Add buy me a coffee

Author: Kosal Ang

README.md

@@ -68,3 +68,5 @@ Rename or copy `.env.example` file to `.env` 1.`php artisan key:generate` to gen
 #### Customer list
 
 ![Customer list](https://raw.githubusercontent.com/angkosal/laravel-pos/master/screenshots/customer_list.png)
+
+[!["Buy Me A Coffee"](https://www.buymeacoffee.com/assets/img/custom_images/orange_img.png)](https://www.buymeacoffee.com/angkosal)