Update composer.json

Author: bigrocs

composer.json

@@ -21,6 +21,7 @@
     "require": {
         "php": "~5.6|~7.0",
         "corecmf/admin": "^1.3",
+        "symfony/event-dispatcher": "^2.8",
         "ignited/laravel-omnipay": "^2.3",
         "lokielse/omnipay-unionpay": "^0.3",
         "lokielse/omnipay-wechatpay": "^1.0",