Support Laravel 5.4

Author: GrahamCampbell

composer.json

@@ -11,8 +11,8 @@
     ],
     "require": {
         "php": ">=5.5.9",
-        "illuminate/contracts": "5.1.*|5.2.*|5.3.*",
-        "illuminate/support": "5.1.*|5.2.*|5.3.*",
+        "illuminate/contracts": "5.1.*|5.2.*|5.3.*|5.4.*",
+        "illuminate/support": "5.1.*|5.2.*|5.3.*|5.4.*",
         "parse/php-sdk": "^1.2.1"
     },
     "require-dev": {