Allow symfony/http-foundation ^5 (#3)

* Allow symfony/http-foundation ^5

Author: bramus

composer.json

@@ -21,7 +21,7 @@
     },
     "require": {
         "php": "^7.1",
-        "symfony/http-foundation": "^2.7 || ^3.0 || ^4.0"
+        "symfony/http-foundation": "^2.7 || ^3.0 || ^4.0 || ^5.0"
     },
     "require-dev": {
         "phpunit/phpunit": "^6.5"