title: Please explain this code is for Articles.events.publish
body: <p>I'm looking for help to understand this code from the sample module Articles in the mean.io generated app. I can't figure out what Articles.events.publish is for.</p>
  
  <p>file: packages/core/articles/server/controllers/articles.js</p>
  
  <pre><code>     create: function(req, res) {
          var article = new Article(req.body);
          article.user = req.user;
  
          article.save(function(err) {
              if (err) {
                  return res.status(500).json({
                      error: 'Cannot save the article'
                  });
              }
  
              Articles.events.publish({
                  action: 'created',
                  user: {
                      name: req.user.name
                  },
                  url: config.hostname + '/articles/' + article._id,
                  name: article.title
              });
  
              res.json(article);
          });
      }
  </code></pre>