update README

Author: cebe

README.md

@@ -15,10 +15,9 @@ This application template consists of 3 application tiers:
 
 ## Setup
 
-    git clone https://github.com/cebe/yii2-app-api my-api
+    composer create-project cebe/yii2-app-api my-api
     cd my-api
     cp env.php.dist env.php
-    composer install
 
 ## Generate Code