title: what does express.favicon() do
body: <p>I would like to know what express.favicon() does.
  I seared and could not get the  reasoning.</p>
  
  <p>can any one explain me on this.</p>
  
  <pre><code>app.use(express.favicon());
  </code></pre>
  
  <p>I read some link that this command will do a ignore of GET/favicon.ico.
  I am looking for understanding more about this like?where is the function: express.favicon() defined and all those information, I did checked in the expresss website could not find the declaration/definition of this function</p>