MAGETWO-63065: Update pdepend to 2.4.0

Author: buskamuza

composer.json

@@ -72,7 +72,7 @@
         "phpunit/phpunit": "4.1.0",
         "squizlabs/php_codesniffer": "1.5.3",
         "phpmd/phpmd": "@stable",
-        "pdepend/pdepend": "2.2.2",
+        "pdepend/pdepend": "2.4.0",
         "friendsofphp/php-cs-fixer": "~1.2",
         "lusitanian/oauth": "~0.3 <=0.7.0",
         "sebastian/phpcpd": "2.0.0"