Merge branch '3.4' into 4.4

* 3.4:
  Allow more PHP versions

Author: fabpot

composer.json

@@ -4,7 +4,7 @@
     "license": "MIT",
     "description": "A skeleton to start a new Symfony website",
     "require": {
-        "php": "^7.1.3",
+        "php": ">=7.1.3",
         "ext-ctype": "*",
         "ext-iconv": "*",
         "symfony/flex": "^1.3.1"