Use Laravel's "config" helper to get model's config

[pavgra]

Use Laravel's "config" helper to get model's config (to retrieve all changes that might be done to config during app runtime)

[KingMob]

Unfortunately, this presents an obstacle to fixing #980, since heavier reliance on Laravel's config() will mean more work to avoid breaking artisan config:cache. As Laravel currently stands, it can't handle anonymous functions in the config files when caching.