Merge pull request #82 from GregorVoelkl/upgrade-l55

update composer packages to match laravel 5.5 requirements

composer.json

@@ -11,7 +11,7 @@
     ],
     "require": {
         "php": ">=5.5.5",
-        "illuminate/support": "5.0.*|5.1.*|5.2.*|5.3.*|5.4.*",
+        "illuminate/support": "5.0.*|5.1.*|5.2.*|5.3.*|5.4.*|5.5.*",
         "guzzlehttp/guzzle": "^6.2"
     },
     "autoload": {