title: Logging in gunicorn log file is not detailed
body: <p>I'm setting log level to 'debug' which I recall is the most verbose, however I'm only getting lines like this, even when an exception is thrown:</p>
  
  <pre><code>[2018-04-18 22:08:21 +0000] [23394] [DEBUG] POST /json
  </code></pre>
  
  <p>My startup command is this:</p>
  
  <pre><code>gunicorn  --log-level debug --error-logfile gunicorn_error.log  -D -b 0.0.0.0:5000 forward_to_es:app
  </code></pre>
  
  <p>Thanks for any suggestions.</p>