Update dependencies!

Author: Christoph Rumpel

README.md

@@ -1,4 +1,4 @@
-# Twitter notification channel for Laravel 5.3
+# Twitter notification channel for Laravel 5.4
 
 [![Latest Version on Packagist](https://img.shields.io/packagist/v/laravel-notification-channels/twitter.svg?style=flat-square)](https://packagist.org/packages/laravel-notification-channels/twitter)
 [![Software License](https://img.shields.io/badge/license-MIT-brightgreen.svg?style=flat-square)](LICENSE.md)
@@ -9,7 +9,7 @@
 [![Code Coverage](https://img.shields.io/scrutinizer/coverage/g/laravel-notification-channels/twitter/master.svg?style=flat-square)](https://scrutinizer-ci.com/g/laravel-notification-channels/twitter/?branch=master)
 [![Total Downloads](https://img.shields.io/packagist/dt/laravel-notification-channels/twitter.svg?style=flat-square)](https://packagist.org/packages/laravel-notification-channels/twitter)
 
-This package makes it easy to send notifications using [Twitter](https://dev.twitter.com/rest/public) with Laravel 5.3.
+This package makes it easy to send notifications using [Twitter](https://dev.twitter.com/rest/public) with Laravel 5.4.
 
 ## Contents
 

composer.json

@@ -13,15 +13,15 @@
     ],
     "require": {
         "php": ">=5.6.4",
-        "abraham/twitteroauth": "^0.6.4",
-        "illuminate/notifications": "5.4.*",
-        "illuminate/support": "~5.1",
+        "abraham/twitteroauth": "^0.7.2",
+        "illuminate/notifications": "5.3.*|5.4.*",
+        "illuminate/support": "5.1.*|5.2.*|5.3.*|5.4.*",
         "kylewm/brevity": "^0.2.9"
     },
     "require-dev": {
         "mockery/mockery": "^0.9.5",
-        "phpunit/phpunit": "4.*",
-        "orchestra/testbench": "3.4.*"
+        "phpunit/phpunit": "~5.7",
+        "orchestra/testbench": "~3.3|~3.4"
     },
     "autoload": {
         "psr-4": {