Wraps GitHub User Emails API.
Requires authentication.
$emails = $client->currentUser()->emails()->all();
$emails = $client->currentUser()->emails()->allPublic();
$emails = $client->currentUser()->emails()->add(['email1', 'email2']);
$client->currentUser()->emails()->remove(['email1', 'email2']);
$primaryEmail = $client->currentUser()->emails()->toggleVisibility();