public function versions() {
        $this->hr(1);

        $versions = array();

        if ($this->versions) {
            foreach ($this->versions as $version => $title) {
                if (in_array($version, $this->complete)) {
                    $this->out('[x] ' . $title);
                } else {
                    $this->out(sprintf('[%s] <info>%s</info>', $version, $title));
                    $versions[] = $version;
                }
            }
        } else {
            $this->err('<error>No versions found</error>');
            return;
        }

        $this->out('[E]xit');
        $this->out();

        $versions[] = 'E';
        $answer = strtoupper($this->in('Which version do you want to upgrade to?', $versions));

        if ($answer === 'E') {
            exit();
        }

        $this->to($answer);
    }