Fix byref parameter passing

[puetzk]

• zend_parse_parameters should use the / qualfier to make sure it use SEPARATE_ZVAL_IF_NOT_REF; otherwise we could have a zval* to something that is not supposed to be mutable.
• ZEND_ARG_INFO(1, ...) must be used to indicate when an argument is pass-by-ref, otherwise it won't copy the value back https://github.com/php/php-src/blob/master/README.PARAMETER_PARSING_API

This makes the error messages come back for me, but it's only based on some googling that turned up http://news.php.net/php.internals/97194 and https://github.com/php/php-src/blob/master/README.PARAMETER_PARSING_API. I really have no idea what I'm doing in php, much less in internals like this :-)

[amishmm]

Done. Thanks