Allow Symfony 5.x dependencies (#2)

Author: mpdude

composer.json

@@ -12,11 +12,11 @@
     ],
 
     "require": {
-        "php": ">=5.3.0",
-        "symfony/config": "^2.4|^3.0|^4.0",
-        "symfony/console": "^2.4|^3.0|^4.0",
-        "symfony/dependency-injection": "^2.4|^3.0|^4.0",
-        "symfony/http-kernel": "^2.4|^3.0|^4.0",
+        "php": "7.2.*|7.4.*",
+        "symfony/config": "^2.4|^3.0|^4.0|^5.0",
+        "symfony/console": "^2.4|^3.0|^4.0|^5.0",
+        "symfony/dependency-injection": "^2.4|^3.0|^4.0|^5.0",
+        "symfony/http-kernel": "^2.4|^3.0|^4.0|^5.0",
         "webfactory/content-mapping": "^3.0"
     },