Get all subdomains, paginated
        Return {'status': true, 'names': [...]} on success
        Return {'error': ...} on error

def rpc_get_all_subdomains( self, offset, count, **conf_info):
        """
        Get all subdomains, paginated
        Return {'status': true, 'names': [...]} on success
        Return {'error': ...} on error
        """
        if not check_offset(offset):
            return {'error': 'invalid offset', 'http_status': 400}

        if not check_count(count, 100):
            return {'error': 'invalid count', 'http_status': 400}

        all_subdomains = get_all_subdomains(offset = offset,
                                            count = count)

        return self.success_response( {'names': all_subdomains} )