open_basedir_for_include

The PDM recommendation covering the removal of safe_mode included a note on expanding the role of open_basedir. To that end, I'd like to propose introducing a new ini option: open_basedir_for_include which would allow using include/require(_once) on an expanded set of directories than what open_basedir would otherwise allow. Since php_fopen_wrapper_for_zend() specifies STREAM_OPEN_FOR_INCLUDE, we can catch this option in the plain_files wrapper and expand the open_basedir check to allow specifying the alternate INI option (when set of course). Obviously if this new option were left unset and the regular open_basedir were set, we'd still use that for full BC. If noone objects I'll add this functionality in between unicode related patches in a week or so. -Sara