diff --git a/composer.lock b/composer.lock
index 44e0023..3fc3af2 100644
--- a/composer.lock
+++ b/composer.lock
@@ -4,7 +4,7 @@
         "Read more about it at https://getcomposer.org/doc/01-basic-usage.md#installing-dependencies",
         "This file is @generated automatically"
     ],
-    "content-hash": "d8f53252d6ecc4db169ec0a999fb3181",
+    "content-hash": "385a6896e5fc164d5f6b6235b204c267",
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         {
             "name": "symfony/polyfill-mbstring",
@@ -65,40 +65,101 @@
             ],
             "time": "2018-08-06T14:22:27+00:00"
         },
+        {
+            "name": "symfony/polyfill-php72",
+            "version": "v1.9.0",
+            "source": {
+                "type": "git",
+                "url": "https://github.com/symfony/polyfill-php72.git",
+                "reference": "95c50420b0baed23852452a7f0c7b527303ed5ae"
+            },
+            "dist": {
+                "type": "zip",
+                "url": "https://api.github.com/repos/symfony/polyfill-php72/zipball/95c50420b0baed23852452a7f0c7b527303ed5ae",
+                "reference": "95c50420b0baed23852452a7f0c7b527303ed5ae",
+                "shasum": ""
+            },
+            "require": {
+                "php": ">=5.3.3"
+            },
+            "type": "library",
+            "extra": {
+                "branch-alias": {
+                    "dev-master": "1.9-dev"
+                }
+            },
+            "autoload": {
+                "psr-4": {
+                    "Symfony\\Polyfill\\Php72\\": ""
+                },
+                "files": [
+                    "bootstrap.php"
+                ]
+            },
+            "notification-url": "https://packagist.org/downloads/",
+            "license": [
+                "MIT"
+            ],
+            "authors": [
+                {
+                    "name": "Nicolas Grekas",
+                    "email": "p@tchwork.com"
+                },
+                {
+                    "name": "Symfony Community",
+                    "homepage": "https://symfony.com/contributors"
+                }
+            ],
+            "description": "Symfony polyfill backporting some PHP 7.2+ features to lower PHP versions",
+            "homepage": "https://symfony.com",
+            "keywords": [
+                "compatibility",
+                "polyfill",
+                "portable",
+                "shim"
+            ],
+            "time": "2018-08-06T14:22:27+00:00"
+        },
         {
             "name": "symfony/var-dumper",
-            "version": "v3.4.15",
+            "version": "v4.1.4",
             "source": {
                 "type": "git",
                 "url": "https://github.com/symfony/var-dumper.git",
-                "reference": "f62a394bd3de96f2f5e8f4c7d685035897fb3cb3"
+                "reference": "a05426e27294bba7b0226ffc17dd01a3c6ef9777"
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-                "reference": "f62a394bd3de96f2f5e8f4c7d685035897fb3cb3",
+                "url": "https://api.github.com/repos/symfony/var-dumper/zipball/a05426e27294bba7b0226ffc17dd01a3c6ef9777",
+                "reference": "a05426e27294bba7b0226ffc17dd01a3c6ef9777",
                 "shasum": ""
             },
             "require": {
-                "php": "^5.5.9|>=7.0.8",
-                "symfony/polyfill-mbstring": "~1.0"
+                "php": "^7.1.3",
+                "symfony/polyfill-mbstring": "~1.0",
+                "symfony/polyfill-php72": "~1.5"
             },
             "conflict": {
-                "phpunit/phpunit": "<4.8.35|<5.4.3,>=5.0"
+                "phpunit/phpunit": "<4.8.35|<5.4.3,>=5.0",
+                "symfony/console": "<3.4"
             },
             "require-dev": {
                 "ext-iconv": "*",
+                "symfony/process": "~3.4|~4.0",
                 "twig/twig": "~1.34|~2.4"
             },
             "suggest": {
                 "ext-iconv": "To convert non-UTF-8 strings to UTF-8 (or symfony/polyfill-iconv in case ext-iconv cannot be used).",
                 "ext-intl": "To show region name in time zone dump",
-                "ext-symfony_debug": ""
+                "symfony/console": "To use the ServerDumpCommand and/or the bin/var-dump-server script"
             },
+            "bin": [
+                "Resources/bin/var-dump-server"
+            ],
             "type": "library",
             "extra": {
                 "branch-alias": {
-                    "dev-master": "3.4-dev"
+                    "dev-master": "4.1-dev"
                 }
             },
             "autoload": {
@@ -132,7 +193,7 @@
                 "debug",
                 "dump"
             ],
-            "time": "2018-07-26T11:19:56+00:00"
+            "time": "2018-08-02T09:24:26+00:00"
         }
     ],
     "packages-dev": [
@@ -975,16 +1036,16 @@
         },
         {
             "name": "phpunit/phpunit",
-            "version": "7.3.3",
+            "version": "7.3.4",
             "source": {
                 "type": "git",
                 "url": "https://github.com/sebastianbergmann/phpunit.git",
-                "reference": "1bd5629cccfb2c0a9ef5474b4ff772349e1ec898"
+                "reference": "0356331bf62896dc56e3a15030b23b73f38b2935"
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                 "type": "zip",
-                "url": "https://api.github.com/repos/sebastianbergmann/phpunit/zipball/1bd5629cccfb2c0a9ef5474b4ff772349e1ec898",
-                "reference": "1bd5629cccfb2c0a9ef5474b4ff772349e1ec898",
+                "url": "https://api.github.com/repos/sebastianbergmann/phpunit/zipball/0356331bf62896dc56e3a15030b23b73f38b2935",
+                "reference": "0356331bf62896dc56e3a15030b23b73f38b2935",
                 "shasum": ""
             },
             "require": {
@@ -1055,7 +1116,7 @@
                 "testing",
                 "xunit"
             ],
-            "time": "2018-09-01T15:49:55+00:00"
+            "time": "2018-09-05T09:58:53+00:00"
         },
         {
             "name": "sebastian/code-unit-reverse-lookup",