Address comments

Author: minggangw

scripts/npmjs-readme.md

@@ -58,10 +58,10 @@ TypeScript example:
 ```typescript
 import * as rclnodejs from 'rclnodejs';
 rclnodejs.init().then(() => {
-  const node = new rclnodejs.Node('publisher_example_node');
+  const node = rclnodejs.createNode('publisher_example_node');
   const publisher = node.createPublisher('std_msgs/msg/String', 'topic');
   publisher.publish(`Hello ROS 2 from rclnodejs`);
-  node.spin();
+  rclnodejs.spin(node);
 });
 ```