feat: update php version

sabakugaara · sabakugaara · commit 7890935471b1 · 2016-12-14T10:47:45.000+08:00
diff --git a/composer.json b/composer.json
@@ -7,7 +7,7 @@
     "homepage": "https://github.com/upyun/php-sdk/",
     "license": "MIT",
     "require": {
-        "php": ">=5.3.0",
+        "php": ">=5.5.0",
         "ext-curl": "*",
         "guzzlehttp/guzzle": "~6.0"
     },
