Added laravel 5.8 support

composer.json

@@ -11,7 +11,7 @@
     ],
     "require": {
         "php": ">=5.5.5",
-        "illuminate/support": "5.0.*|5.1.*|5.2.*|5.3.*|5.4.*|5.5.*|5.6.*|5.7.*",
+        "illuminate/support": "5.0.*|5.1.*|5.2.*|5.3.*|5.4.*|5.5.*|5.6.*|5.7.*|5.8.*",
         "guzzlehttp/guzzle": "^6.2"
     },
     "require-dev": {