update composer.json php version..

composer.json

@@ -10,7 +10,7 @@
         }
     ],
     "require": {
-        "php": ">=5.4.0",
+        "php": ">=5.5.5",
         "illuminate/support": "5.0.*|5.1.*|5.2.*|5.3.*",
         "guzzlehttp/guzzle": "^6.2"
     },