ecshop二次开发：Non-static method cls_image::gd_version() should not be called statically in的解决

PHP5.4会报如下错误

Non-static method cls_image::gd_version() should not be called statically in

解决方法：

1）将function gd_version()改成static function gd_version()即可。

2）或者将install/includes/lib_installer.php中的第31行return cls_image::gd_version();改成：

$p = new cls_image();return $p->gd_version();