Alter the information parsed from module and theme .info files
This hook is invoked in _system_rebuild_module_data() and in _system_rebuild_theme_data(). A module may implement this hook in order to add to or alter the data generated by reading the .info file with drupal_parse_info_file().
$info: The .info file contents, passed by reference so that it can be altered.
$file: Full information about the module or theme, including $file->name, and $file->filename
$type: Either 'module' or 'theme', depending on the type of .info file that was passed.
Note: this list is generated by pattern matching, so it may include some functions that are not actually implementations of this hook.
function hook_system_info_alter(&$info, $file, $type) {
// Only fill this in if the .info file does not define a 'datestamp'.
if (empty($info['datestamp'])) {
$info['datestamp'] = filemtime($file->filename);
}
}