Add support for Symfony 5

Author: jasonmccreary

composer.json

@@ -8,7 +8,7 @@
     ],
     "license": "MIT",
     "require": {
-        "symfony/yaml": "^4.3",
+        "symfony/yaml": "^4.3|^5.0",
         "illuminate/console": "^6.0",
         "illuminate/filesystem": "^6.0",
         "illuminate/support": "^6.0"