Impero is command line manager.
The best way to install is to use the composer by command:
composer require newclass/impero
composer install
use Impero\CommandExecutor;
$executor = new CommandExecutor();
$executor->register(new MyCommand()); //class implemented Impero\CommandInterface
$executor->register(new MySecondCommand()); //class implemented Impero\CommandInterface
$executor->execute($argv);
php ./vendor/bin/phpunit