Fixed laravel logo link

Author: vuongxuongminh

README.md

@@ -1,5 +1,5 @@
 <p align="center">
-    <a href="https://github.com/yiisoft" target="_blank">
+    <a href="https://github.com/laravel" target="_blank">
         <img src="https://avatars0.githubusercontent.com/u/958072" height="100px">
     </a>
     <h1 align="center">Laravel Number To Words</h1>