Feature request: clone starred repositories of a user

Thanks for this awesome repo! 🙌
I’d like to suggest a new feature: the ability to clone all repositories starred by a given user.
This could be configured via an option in the config file. For example:
```yaml
# options: all, owner, member, stars
GHORG_XXX_USER_OPTION = stars
```
With this option set to `stars`, the tool would clone all repositories starred by the specified user.