Add init command

TODO list:
- [x] basic config file (server, project, and files)
- [x] add port parameter
- [x] add use_ssl parameter
- [x] create project by api

We could add the default pattern of a symfony2 app. Thoughts?
It would be nice to have a preview of the dump before writing in the file, eg.:
```
$content = Yaml::dump($config, 3);
echo $content;
if (!$dialog->askConfirmation('Do you confirm generation')) {
    return 1;
}
```