composer: bump to PHP 5.3, PHPUnit 4.7

Author: Tomáš Votruba

composer.json

@@ -10,11 +10,11 @@
         {"name": "Steve Müller", "email": "st.mueller@dzh-online.de"}
     ],
     "require": {
-        "php": ">=5.1.2"
+        "php": ">=5.3"
     },
     "require-dev": {
         "squizlabs/php_codesniffer": "1.*",
-        "phpunit/phpunit": "~3.7"
+        "phpunit/phpunit": "~4.7"
     },
     "target-dir": "Doctrine"
 }