diff --git a/api/composer.json b/api/composer.json
index af1cbfdf..65f65522 100644
--- a/api/composer.json
+++ b/api/composer.json
@@ -18,7 +18,9 @@
     "php-http/guzzle6-adapter": "^1.1",
     "php-http/message": "^1.5",
     "php-http/curl-client": "^1.7",
-    "guzzlehttp/psr7": "^1.3",
+    "mike-koch/psr7": "1.4.2.1",
+    "mike-koch/promises": "1.3.1.1",
+    "mike-koch/guzzle": "6.3.0.2",
     "mike-koch/php-di": "4.4.11",
     "doctrine/annotations": "1.2"
   }
diff --git a/api/composer.lock b/api/composer.lock
index 2fdfc9ea..a32e724c 100644
--- a/api/composer.lock
+++ b/api/composer.lock
@@ -4,7 +4,7 @@
         "Read more about it at https://getcomposer.org/doc/01-basic-usage.md#composer-lock-the-lock-file",
         "This file is @generated automatically"
     ],
-    "content-hash": "5259191309e50288eeb2370dd4f35c5f",
+    "content-hash": "b0779eaecb8e2dd1bb24f552b58c3ed2",
     "packages": [
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             "name": "clue/stream-filter",
@@ -518,6 +518,75 @@
             "description": "The Mailgun SDK provides methods for all API functions.",
             "time": "2017-06-20T19:56:09+00:00"
         },
+        {
+            "name": "mike-koch/guzzle",
+            "version": "6.3.0.2",
+            "source": {
+                "type": "git",
+                "url": "https://github.com/mike-koch/guzzle.git",
+                "reference": "1f44938cc111eac200633acfa6f52869fbb7f3c7"
+            },
+            "dist": {
+                "type": "zip",
+                "url": "https://api.github.com/repos/mike-koch/guzzle/zipball/1f44938cc111eac200633acfa6f52869fbb7f3c7",
+                "reference": "1f44938cc111eac200633acfa6f52869fbb7f3c7",
+                "shasum": ""
+            },
+            "require": {
+                "mike-koch/promises": "1.3.1.1",
+                "mike-koch/psr7": "1.4.2.1",
+                "php": ">=5.3"
+            },
+            "require-dev": {
+                "ext-curl": "*",
+                "phpunit/phpunit": "^4.0 || ^5.0",
+                "psr/log": "^1.0"
+            },
+            "suggest": {
+                "psr/log": "Required for using the Log middleware"
+            },
+            "type": "library",
+            "extra": {
+                "branch-alias": {
+                    "dev-master": "6.2-dev"
+                }
+            },
+            "autoload": {
+                "files": [
+                    "src/functions_include.php"
+                ],
+                "psr-4": {
+                    "GuzzleHttp\\": "src/"
+                }
+            },
+            "notification-url": "https://packagist.org/downloads/",
+            "license": [
+                "MIT"
+            ],
+            "authors": [
+                {
+                    "name": "Michael Dowling",
+                    "email": "mtdowling@gmail.com",
+                    "homepage": "https://github.com/mtdowling"
+                },
+                {
+                    "name": "Mike Koch",
+                    "homepage": "https://github.com/mike-koch"
+                }
+            ],
+            "description": "Guzzle is a PHP HTTP client library. Forked from guzzle/guzzle for 5.3 compatibility",
+            "homepage": "http://guzzlephp.org/",
+            "keywords": [
+                "client",
+                "curl",
+                "framework",
+                "http",
+                "http client",
+                "rest",
+                "web service"
+            ],
+            "time": "2017-11-07T13:15:47+00:00"
+        },
         {
             "name": "mike-koch/php-di",
             "version": "4.4.11",
@@ -566,6 +635,126 @@
             ],
             "time": "2017-09-08T02:23:09+00:00"
         },
+        {
+            "name": "mike-koch/promises",
+            "version": "1.3.1.1",
+            "source": {
+                "type": "git",
+                "url": "https://github.com/mike-koch/promises.git",
+                "reference": "70fae8812e5c74b4d23f0bf79f56fdca58c70c27"
+            },
+            "dist": {
+                "type": "zip",
+                "url": "https://api.github.com/repos/mike-koch/promises/zipball/70fae8812e5c74b4d23f0bf79f56fdca58c70c27",
+                "reference": "70fae8812e5c74b4d23f0bf79f56fdca58c70c27",
+                "shasum": ""
+            },
+            "require": {
+                "php": ">=5.3.0"
+            },
+            "require-dev": {
+                "phpunit/phpunit": "^4.8.36"
+            },
+            "type": "library",
+            "extra": {
+                "branch-alias": {
+                    "dev-master": "1.4-dev"
+                }
+            },
+            "autoload": {
+                "psr-4": {
+                    "GuzzleHttp\\Promise\\": "src/"
+                },
+                "files": [
+                    "src/functions_include.php"
+                ]
+            },
+            "notification-url": "https://packagist.org/downloads/",
+            "license": [
+                "MIT"
+            ],
+            "authors": [
+                {
+                    "name": "Michael Dowling",
+                    "email": "mtdowling@gmail.com",
+                    "homepage": "https://github.com/mtdowling"
+                },
+                {
+                    "name": "Mike Koch",
+                    "homepage": "https://github.com/mike-koch"
+                }
+            ],
+            "description": "Guzzle promises library, forked from guzzle/promises for PHP 5.3 compatibility",
+            "keywords": [
+                "promise"
+            ],
+            "time": "2017-11-07T13:07:15+00:00"
+        },
+        {
+            "name": "mike-koch/psr7",
+            "version": "1.4.2.1",
+            "source": {
+                "type": "git",
+                "url": "https://github.com/mike-koch/psr7.git",
+                "reference": "a35f28d9377505ba666298d351413e87a035d8b1"
+            },
+            "dist": {
+                "type": "zip",
+                "url": "https://api.github.com/repos/mike-koch/psr7/zipball/a35f28d9377505ba666298d351413e87a035d8b1",
+                "reference": "a35f28d9377505ba666298d351413e87a035d8b1",
+                "shasum": ""
+            },
+            "require": {
+                "php": ">=5.4.0",
+                "psr/http-message": "~1.0"
+            },
+            "provide": {
+                "psr/http-message-implementation": "1.0"
+            },
+            "require-dev": {
+                "phpunit/phpunit": "~4.0"
+            },
+            "type": "library",
+            "extra": {
+                "branch-alias": {
+                    "dev-master": "1.4-dev"
+                }
+            },
+            "autoload": {
+                "psr-4": {
+                    "GuzzleHttp\\Psr7\\": "src/"
+                },
+                "files": [
+                    "src/functions_include.php"
+                ]
+            },
+            "notification-url": "https://packagist.org/downloads/",
+            "license": [
+                "MIT"
+            ],
+            "authors": [
+                {
+                    "name": "Michael Dowling",
+                    "email": "mtdowling@gmail.com",
+                    "homepage": "https://github.com/mtdowling"
+                },
+                {
+                    "name": "Tobias Schultze",
+                    "homepage": "https://github.com/Tobion"
+                }
+            ],
+            "description": "PSR-7 message implementation that also provides common utility methods",
+            "keywords": [
+                "http",
+                "message",
+                "request",
+                "response",
+                "stream",
+                "uri",
+                "url"
+            ],
+            "time": "2017-11-07T02:59:52+00:00"
+        },
         {
             "name": "myclabs/php-enum",
             "version": "1.5.2",
@@ -1235,16 +1424,16 @@
         },
         {
             "name": "phpmailer/phpmailer",
-            "version": "v5.2.25",
+            "version": "v5.2.26",
             "source": {
                 "type": "git",
                 "url": "https://github.com/PHPMailer/PHPMailer.git",
-                "reference": "2baf20b01690fba8cf720c1ebcf9b988eda50915"
+                "reference": "70362997bda4376378be7d92d81e2200550923f7"
             },
             "dist": {
                 "type": "zip",
-                "url": "https://api.github.com/repos/PHPMailer/PHPMailer/zipball/2baf20b01690fba8cf720c1ebcf9b988eda50915",
-                "reference": "2baf20b01690fba8cf720c1ebcf9b988eda50915",
+                "url": "https://api.github.com/repos/PHPMailer/PHPMailer/zipball/70362997bda4376378be7d92d81e2200550923f7",
+                "reference": "70362997bda4376378be7d92d81e2200550923f7",
                 "shasum": ""
             },
             "require": {
@@ -1308,7 +1497,7 @@
                 }
             ],
             "description": "PHPMailer is a full-featured email creation and transfer class for PHP",
-            "time": "2017-08-28T11:12:07+00:00"
+            "time": "2017-11-04T09:26:05+00:00"
         },
         {
             "name": "psr/container",
@@ -2033,16 +2222,16 @@
         },
         {
             "name": "phpunit/php-code-coverage",
-            "version": "5.2.2",
+            "version": "5.2.3",
             "source": {
                 "type": "git",
                 "url": "https://github.com/sebastianbergmann/php-code-coverage.git",
-                "reference": "8ed1902a57849e117b5651fc1a5c48110946c06b"
+                "reference": "8e1d2397d8adf59a3f12b2878a3aaa66d1ab189d"
             },
             "dist": {
                 "type": "zip",
-                "url": "https://api.github.com/repos/sebastianbergmann/php-code-coverage/zipball/8ed1902a57849e117b5651fc1a5c48110946c06b",
-                "reference": "8ed1902a57849e117b5651fc1a5c48110946c06b",
+                "url": "https://api.github.com/repos/sebastianbergmann/php-code-coverage/zipball/8e1d2397d8adf59a3f12b2878a3aaa66d1ab189d",
+                "reference": "8e1d2397d8adf59a3f12b2878a3aaa66d1ab189d",
                 "shasum": ""
             },
             "require": {
@@ -2051,7 +2240,7 @@
                 "php": "^7.0",
                 "phpunit/php-file-iterator": "^1.4.2",
                 "phpunit/php-text-template": "^1.2.1",
-                "phpunit/php-token-stream": "^1.4.11 || ^2.0",
+                "phpunit/php-token-stream": "^2.0",
                 "sebastian/code-unit-reverse-lookup": "^1.0.1",
                 "sebastian/environment": "^3.0",
                 "sebastian/version": "^2.0.1",
@@ -2093,7 +2282,7 @@
                 "testing",
                 "xunit"
             ],
-            "time": "2017-08-03T12:40:43+00:00"
+            "time": "2017-11-03T13:47:33+00:00"
         },
         {
             "name": "phpunit/php-file-iterator",
@@ -2471,30 +2660,30 @@
         },
         {
             "name": "sebastian/comparator",
-            "version": "2.0.2",
+            "version": "2.1.0",
             "source": {
                 "type": "git",
                 "url": "https://github.com/sebastianbergmann/comparator.git",
-                "reference": "ae068fede81d06e7bb9bb46a367210a3d3e1fe6a"
+                "reference": "1174d9018191e93cb9d719edec01257fc05f8158"
             },
             "dist": {
                 "type": "zip",
-                "url": "https://api.github.com/repos/sebastianbergmann/comparator/zipball/ae068fede81d06e7bb9bb46a367210a3d3e1fe6a",
-                "reference": "ae068fede81d06e7bb9bb46a367210a3d3e1fe6a",
+                "url": "https://api.github.com/repos/sebastianbergmann/comparator/zipball/1174d9018191e93cb9d719edec01257fc05f8158",
+                "reference": "1174d9018191e93cb9d719edec01257fc05f8158",
                 "shasum": ""
             },
             "require": {
                 "php": "^7.0",
                 "sebastian/diff": "^2.0",
-                "sebastian/exporter": "^3.0"
+                "sebastian/exporter": "^3.1"
             },
             "require-dev": {
-                "phpunit/phpunit": "^6.0"
+                "phpunit/phpunit": "^6.4"
             },
             "type": "library",
             "extra": {
                 "branch-alias": {
-                    "dev-master": "2.0.x-dev"
+                    "dev-master": "2.1.x-dev"
                 }
             },
             "autoload": {
@@ -2525,13 +2714,13 @@
                 }
             ],
             "description": "Provides the functionality to compare PHP values for equality",
-            "homepage": "http://www.github.com/sebastianbergmann/comparator",
+            "homepage": "https://github.com/sebastianbergmann/comparator",
             "keywords": [
                 "comparator",
                 "compare",
                 "equality"
             ],
-            "time": "2017-08-03T07:14:59+00:00"
+            "time": "2017-11-03T07:16:52+00:00"
         },
         {
             "name": "sebastian/diff",