title: WP REST API can't set post tags
body: <p>I create post with WP REST API but can't set tags for the post.</p>
  
  <pre><code>var post_data = {
      'author': 1,
      'title': 'My title',
      'content': 'My content',
      'status': 'publish',
      'tags': ['tags1','tags2'],
  }
  </code></pre>
  
  <p>That code return error: <code>Invalid parameter(s): tags</code></p>
  
  <p>Can you explain wheres wrong?</p>