ToDo : Get config file value if doesn't exist in Setting

[AEK-BKF]

Hi,

Thank so much for this nice package,
I've a suggestion :
It's a good idea to add a function that retrieves a value from a file config when it doesn't exist in Setting table,
Example:
$value = Setting::get('file.name'); // It returns config('file.name').

Thanks :)

[youchenlee]

Excellent idea.

The long one would be use the default value parameter, it's very redundant:

$value = Setting::get('file.name', config('file.name'));

perhaps adding a setFallback() method, and can be use like:

Settings::setFallback(function ($key, $default) {
    return config($key, $default);
});

what do you think? @AEK-BKF