How to set up for developers

1. Get the repo (e.g. by git clone).
2. composer install to install libraries and dependencies.
3. Set up file sample.env.local.php. Its instruction is inside the file.
4. Set up configurations in app/config.
5. Set up configurations in bootstrap/start.php.
6. Run the migrations and seeds: php artisan migrate and php artisan db:seed.
7. composer dump -o to generate optimized autoload file.
8. Done.