title: Rails.logger does not log in Rails 5
body: <p>I have a Rails 5 app and I want to use the logger.</p>
  
  <p>So I wrote:</p>
  
  <pre><code>Rails.logger.error '123'
  </code></pre>
  
  <p>But when I run it (I am sure that it runs because there are other commands in the same method that are being executed) I don't see any log. Neither in the terminal where the server (rails s) runs, nor in my log/development.log file.</p>
  
  <p>What could be happening here?</p>