Fixed missing 'compile' command when running php artisan optimize in 4.1

Gotten this error today, probably due to latest changes to artisan:

```
[2013-11-29 17:19:23] local.ERROR: exception 'InvalidArgumentException' with message 'Command "compile" is not defined.

Did you mean this?
    clear-compiled' in /var/laravel/vendor/symfony/console/Symfony/Component/Console/Application.php:562
Stack trace:
#0 /var/laravel/vendor/laravel/framework/src/Illuminate/Console/Command.php(136): Symfony\Component\Console\Application->find('compile')
#1 /var/laravel/vendor/laravel/framework/src/Illuminate/Foundation/Console/OptimizeCommand.php(82): Illuminate\Console\Command->callSilent('compile', Array)
#2 /var/laravel/vendor/laravel/framework/src/Illuminate/Foundation/Console/OptimizeCommand.php(59): Illuminate\Foundation\Console\OptimizeCommand->compileClasses()
#3 /var/laravel/vendor/laravel/framework/src/Illuminate/Console/Command.php(108): Illuminate\Foundation\Console\OptimizeCommand->fire()
#4 /var/laravel/vendor/symfony/console/Symfony/Component/Console/Command/Command.php(241): Illuminate\Console\Command->execute(Object(Symfony\Component\Console\Input\ArgvInput), Object(Symfony\Component\Console\Output\ConsoleOutput))
#5 /var/laravel/vendor/laravel/framework/src/Illuminate/Console/Command.php(96): Symfony\Component\Console\Command\Command->run(Object(Symfony\Component\Console\Input\ArgvInput), Object(Symfony\Component\Console\Output\ConsoleOutput))
#6 /var/laravel/vendor/symfony/console/Symfony/Component/Console/Application.php(881): Illuminate\Console\Command->run(Object(Symfony\Component\Console\Input\ArgvInput), Object(Symfony\Component\Console\Output\ConsoleOutput))
#7 /var/laravel/vendor/symfony/console/Symfony/Component/Console/Application.php(191): Symfony\Component\Console\Application->doRunCommand(Object(Illuminate\Foundation\Console\OptimizeCommand), Object(Symfony\Component\Console\Input\ArgvInput), Object(Symfony\Component\Console\Output\ConsoleOutput))
#8 /var/laravel/vendor/symfony/console/Symfony/Component/Console/Application.php(121): Symfony\Component\Console\Application->doRun(Object(Symfony\Component\Console\Input\ArgvInput), Object(Symfony\Component\Console\Output\ConsoleOutput))
#9 /var/laravel/artisan(59): Symfony\Component\Console\Application->run()
#10 {main} [] []
```

Signed-off-by: crynobone <crynobone@gmail.com>