Add roave/security-advisories

This package blocks the installation of vulnerable packages

Author: Bruno Vitorino

composer.json

@@ -27,7 +27,8 @@
     "tijsverkoyen/css-to-inline-styles": "^2.2"
   },
   "require-dev": {
-    "phpunit/phpunit": "^5.7"
+    "phpunit/phpunit": "^5.7",
+    "roave/security-advisories": "dev-master"
   },
   "autoload": {
     "psr-0": { "SumoCoders\\FrameworkCoreBundle": "" }