for making package refer link http://laraveldaily.com/how-to-create-a-laravel-5-package-in-10-easy-steps/

In main composer.json put

"require": { "laraveltest/testpkg": "*@dev" }

"psr-4": { "App\": "app/", "Laraveltest\Testpkg\": "vendor/laraveltest/testpkg/src" }

add this "Laraveltest\Testpkg\TimezonesServiceProvider::class" in app/config.php

make a blank folder with name "database" in laraveltest/testpkg/database

run command "composer update" on terminal