Composer update

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": "d92a71980effd610713e1eabe0cde31a",
+    "content-hash": "cf25345b5d84c3622c3d086ff147283c",
     "packages": [],
     "packages-dev": [
         {
@@ -1268,16 +1268,16 @@
         },
         {
             "name": "nexmo/client",
-            "version": "1.6.0",
+            "version": "1.6.1",
             "source": {
                 "type": "git",
                 "url": "https://github.com/Nexmo/nexmo-php.git",
-                "reference": "01809cc1e17a5af275913c49bb5d444eb6cc06d4"
+                "reference": "3dc03ca1dab726a23b757110897740e54304fc65"
             },
             "dist": {
                 "type": "zip",
-                "url": "https://api.github.com/repos/Nexmo/nexmo-php/zipball/01809cc1e17a5af275913c49bb5d444eb6cc06d4",
-                "reference": "01809cc1e17a5af275913c49bb5d444eb6cc06d4",
+                "url": "https://api.github.com/repos/Nexmo/nexmo-php/zipball/3dc03ca1dab726a23b757110897740e54304fc65",
+                "reference": "3dc03ca1dab726a23b757110897740e54304fc65",
                 "shasum": ""
             },
             "require": {
@@ -1312,7 +1312,7 @@
                 }
             ],
             "description": "PHP Client for using Nexmo's API.",
-            "time": "2018-12-17T10:47:50+00:00"
+            "time": "2019-01-02T09:06:47+00:00"
         },
         {
             "name": "opis/closure",