When running an Artisan task from within your application using `Command::run`, it fails when the same task is ran more than once. Every time the task is resolved, its file is included using `require` leading to duplicate class definitions. By using `require_once` this problem is avoided.

Signed-off-by: Chris Berthe <chrisberthe@gmail.com>

Went ahead and just register the config.load event with Laravel on every request and default to the file implementation.

Signed-off-by: Taylor Otwell <taylorotwell@gmail.com>