Console Integration
Register you console command classes in $GLOBALS['CONSOLE_CMD'] within your config.php., (*1)
config.php, (*2)
<?php
$GLOBALS['CONSOLE_CMD'][] = 'Acme\Command\GreetCommand';
GreetCommand.php, (*3)
<?php
namespace = Acme\Command;
class GreetCommand extends \Symfony\Component\Console\Command\Command
{
    protected function configure()
    {
        $this
            ->setName('demo:greet')
            ->setDescription('Greet someone')
            ->addArgument(
                'name',
                InputArgument::OPTIONAL,
                'Who do you want to greet?'
            )
            ->addOption(
                'yell',
                null,
                InputOption::VALUE_NONE,
                'If set, the task will yell in uppercase letters'
            )
        ;
    }
    protected function execute(InputInterface $input, OutputInterface $output)
    {
        $name = $input->getArgument('name');
        if ($name) {
            $text = 'Hello '.$name;
        } else {
            $text = 'Hello';
        }
        if ($input->getOption('yell')) {
            $text = strtoupper($text);
        }
        $output->writeln($text);
    }
}
If you need a more complex setup routine, use the initializeConsole hook., (*4)
config.php, (*5)
<?php
$GLOBALS['TL_HOOKS']['initializeConsole'][] = array('Acme\Console', 'myInitializeConsole');
Console.php, (*6)
<?php
namespace Acme;
use Symfony\Component\Console\Application;
use Acme\Command\GreetCommand;
class Console
{
    public function myInitializeConsole(Application $application)
    {
        $application->add(new GreetCommand());
    }
}
For details see http://symfony.com/doc/2.3/components/console/introduction.html, (*7)