[TASK] Check compatibility with PHP 5.5

Successfully tested with:

PHP 5.5.5-1~dotdeb.1 (cli) (built: Nov  3 2013 21:25:23)
Copyright (c) 1997-2013 The PHP Group
Zend Engine v2.5.0, Copyright (c) 1998-2013 Zend Technologies
    with Zend OPcache v7.0.3-dev, Copyright (c) 1999-2013, by Zend Technologies

Change-Id: I084a0e542c8ad7d2e015fbae7ed3cb66dd94d046
Reviewed-on: https://review.typo3.org/25379
Reviewed-by: Xavier Perseguers
Tested-by: Xavier Perseguers