code: func (s *UsersService) AddEmails(ctx context.Context, emails []string) ([]*UserEmail, *Response, error) {
  	u := "user/emails"
  	req, err := s.client.NewRequest("POST", u, emails)
  	if err != nil {
  		return nil, nil, err
  	}
  
  	var e []*UserEmail
  	resp, err := s.client.Do(ctx, req, &e)
  	if err != nil {
  		return nil, resp, err
  	}
  
  	return e, resp, nil
  }
docs: // AddEmails adds email addresses of the authenticated user.
  //
  // GitHub API docs: https://developer.github.com/v3/users/emails/#add-email-addresses