Add support for folders in $config->statusFiles

[matjazpotocnik]

I would like to do this:

$config->statusFiles('boot', 'modules/somemodule/something.php');

Right now, the folder path is ignored, and you have to copy the file to the site folder manually. Or, even better, add an option to include a file, something like /site/preboot.php in index.php, even before PW boots.