Add fallback support

Fetch the default translation if the current locale doesn't have any translated attributes yet. In the example below the current article doesn't have have the title attribute translated to Swedish yet.

App::setLocale('en');
echo $article->title; // return 'Five Ants Are More than Four Elephants'

App::setLocale('sv');
echo $article->title; // returns 'Five Ants Are More than Four Elephants'

This can be turned off/on in the config.php file.