docs: function probeServer(address, port, callback) {
      address = address || 'localhost';
      port    = port || 443;
  
      pingServer({
          address:  address,
          port:     port,
          attempts: 1,
          timeout:  5000
      }, function(err, data) {
          var available = data.min !== undefined;
          callback(err, available);
      });
  }