Drop PHP5.3.

Author: Hywan

composer.json

@@ -21,7 +21,7 @@
         "source": "http://git.hoa-project.net/"
     },
     "require": {
-        "hoa/core": "~1.0"
+        "hoa/core": "~2.0"
     },
     "target-dir": "Hoa/Visitor",
     "autoload"  : { "psr-0": { "Hoa\\Visitor": "." } }