diff --git a/composer.json b/composer.json
index 24c46af..427e04e 100644
--- a/composer.json
+++ b/composer.json
@@ -8,7 +8,7 @@
         }
     ],
     "require": {
-        "guzzlehttp/guzzle": "6.2.3",
-        "twig/twig": "~1.0"
+        "guzzlehttp/guzzle": "^6",
+        "twig/twig": "^2"
     }
 }
diff --git a/composer.lock b/composer.lock
index 12015c3..0d6604c 100644
--- a/composer.lock
+++ b/composer.lock
@@ -1,23 +1,23 @@
 {
     "_readme": [
         "This file locks the dependencies of your project to a known state",
-        "Read more about it at https://getcomposer.org/doc/01-basic-usage.md#composer-lock-the-lock-file",
+        "Read more about it at https://getcomposer.org/doc/01-basic-usage.md#installing-dependencies",
         "This file is @generated automatically"
     ],
-    "content-hash": "b702a42c8eedad019f88c871628b496b",
+    "content-hash": "7eced2a75010609593705f82da1ed413",
     "packages": [
         {
             "name": "guzzlehttp/guzzle",
-            "version": "6.2.3",
+            "version": "6.3.3",
             "source": {
                 "type": "git",
                 "url": "https://github.com/guzzle/guzzle.git",
-                "reference": "8d6c6cc55186db87b7dc5009827429ba4e9dc006"
+                "reference": "407b0cb880ace85c9b63c5f9551db498cb2d50ba"
             },
             "dist": {
                 "type": "zip",
-                "url": "https://api.github.com/repos/guzzle/guzzle/zipball/8d6c6cc55186db87b7dc5009827429ba4e9dc006",
-                "reference": "8d6c6cc55186db87b7dc5009827429ba4e9dc006",
+                "url": "https://api.github.com/repos/guzzle/guzzle/zipball/407b0cb880ace85c9b63c5f9551db498cb2d50ba",
+                "reference": "407b0cb880ace85c9b63c5f9551db498cb2d50ba",
                 "shasum": ""
             },
             "require": {
@@ -27,13 +27,16 @@
             },
             "require-dev": {
                 "ext-curl": "*",
-                "phpunit/phpunit": "^4.0",
+                "phpunit/phpunit": "^4.8.35 || ^5.7 || ^6.4 || ^7.0",
                 "psr/log": "^1.0"
             },
+            "suggest": {
+                "psr/log": "Required for using the Log middleware"
+            },
             "type": "library",
             "extra": {
                 "branch-alias": {
-                    "dev-master": "6.2-dev"
+                    "dev-master": "6.3-dev"
                 }
             },
             "autoload": {
@@ -66,7 +69,7 @@
                 "rest",
                 "web service"
             ],
-            "time": "2017-02-28T22:50:30+00:00"
+            "time": "2018-04-22T15:46:56+00:00"
         },
         {
             "name": "guzzlehttp/promises",
@@ -235,31 +238,150 @@
             "time": "2016-08-06T14:39:51+00:00"
         },
         {
-            "name": "twig/twig",
-            "version": "v1.34.4",
+            "name": "symfony/polyfill-ctype",
+            "version": "v1.9.0",
             "source": {
                 "type": "git",
-                "url": "https://github.com/twigphp/Twig.git",
-                "reference": "f878bab48edb66ad9c6ed626bf817f60c6c096ee"
+                "url": "https://github.com/symfony/polyfill-ctype.git",
+                "reference": "e3d826245268269cd66f8326bd8bc066687b4a19"
             },
             "dist": {
                 "type": "zip",
-                "url": "https://api.github.com/repos/twigphp/Twig/zipball/f878bab48edb66ad9c6ed626bf817f60c6c096ee",
-                "reference": "f878bab48edb66ad9c6ed626bf817f60c6c096ee",
+                "url": "https://api.github.com/repos/symfony/polyfill-ctype/zipball/e3d826245268269cd66f8326bd8bc066687b4a19",
+                "reference": "e3d826245268269cd66f8326bd8bc066687b4a19",
                 "shasum": ""
             },
             "require": {
                 "php": ">=5.3.3"
             },
-            "require-dev": {
-                "psr/container": "^1.0",
-                "symfony/debug": "~2.7",
-                "symfony/phpunit-bridge": "~3.3@dev"
+            "suggest": {
+                "ext-ctype": "For best performance"
             },
             "type": "library",
             "extra": {
                 "branch-alias": {
-                    "dev-master": "1.34-dev"
+                    "dev-master": "1.9-dev"
+                }
+            },
+            "autoload": {
+                "psr-4": {
+                    "Symfony\\Polyfill\\Ctype\\": ""
+                },
+                "files": [
+                    "bootstrap.php"
+                ]
+            },
+            "notification-url": "https://packagist.org/downloads/",
+            "license": [
+                "MIT"
+            ],
+            "authors": [
+                {
+                    "name": "Symfony Community",
+                    "homepage": "https://symfony.com/contributors"
+                },
+                {
+                    "name": "Gert de Pagter",
+                    "email": "BackEndTea@gmail.com"
+                }
+            ],
+            "description": "Symfony polyfill for ctype functions",
+            "homepage": "https://symfony.com",
+            "keywords": [
+                "compatibility",
+                "ctype",
+                "polyfill",
+                "portable"
+            ],
+            "time": "2018-08-06T14:22:27+00:00"
+        },
+        {
+            "name": "symfony/polyfill-mbstring",
+            "version": "v1.9.0",
+            "source": {
+                "type": "git",
+                "url": "https://github.com/symfony/polyfill-mbstring.git",
+                "reference": "d0cd638f4634c16d8df4508e847f14e9e43168b8"
+            },
+            "dist": {
+                "type": "zip",
+                "url": "https://api.github.com/repos/symfony/polyfill-mbstring/zipball/d0cd638f4634c16d8df4508e847f14e9e43168b8",
+                "reference": "d0cd638f4634c16d8df4508e847f14e9e43168b8",
+                "shasum": ""
+            },
+            "require": {
+                "php": ">=5.3.3"
+            },
+            "suggest": {
+                "ext-mbstring": "For best performance"
+            },
+            "type": "library",
+            "extra": {
+                "branch-alias": {
+                    "dev-master": "1.9-dev"
+                }
+            },
+            "autoload": {
+                "psr-4": {
+                    "Symfony\\Polyfill\\Mbstring\\": ""
+                },
+                "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 for the Mbstring extension",
+            "homepage": "https://symfony.com",
+            "keywords": [
+                "compatibility",
+                "mbstring",
+                "polyfill",
+                "portable",
+                "shim"
+            ],
+            "time": "2018-08-06T14:22:27+00:00"
+        },
+        {
+            "name": "twig/twig",
+            "version": "v2.5.0",
+            "source": {
+                "type": "git",
+                "url": "https://github.com/twigphp/Twig.git",
+                "reference": "6a5f676b77a90823c2d4eaf76137b771adf31323"
+            },
+            "dist": {
+                "type": "zip",
+                "url": "https://api.github.com/repos/twigphp/Twig/zipball/6a5f676b77a90823c2d4eaf76137b771adf31323",
+                "reference": "6a5f676b77a90823c2d4eaf76137b771adf31323",
+                "shasum": ""
+            },
+            "require": {
+                "php": "^7.0",
+                "symfony/polyfill-ctype": "^1.8",
+                "symfony/polyfill-mbstring": "~1.0"
+            },
+            "require-dev": {
+                "psr/container": "^1.0",
+                "symfony/debug": "^2.7",
+                "symfony/phpunit-bridge": "^3.3"
+            },
+            "type": "library",
+            "extra": {
+                "branch-alias": {
+                    "dev-master": "2.5-dev"
                 }
             },
             "autoload": {
@@ -288,16 +410,16 @@
                 },
                 {
                     "name": "Twig Team",
-                    "homepage": "http://twig.sensiolabs.org/contributors",
+                    "homepage": "https://twig.symfony.com/contributors",
                     "role": "Contributors"
                 }
             ],
             "description": "Twig, the flexible, fast, and secure template language for PHP",
-            "homepage": "http://twig.sensiolabs.org",
+            "homepage": "https://twig.symfony.com",
             "keywords": [
                 "templating"
             ],
-            "time": "2017-07-04T13:19:31+00:00"
+            "time": "2018-07-13T07:18:09+00:00"
         }
     ],
     "packages-dev": [],