Enable gunicorn debugging

Author: jsbroks

docker/production/Dockerfile

@@ -35,4 +35,4 @@ RUN pip install -r requirements.txt
 RUN pip install pycocotools
 
 EXPOSE 5000
-CMD gunicorn -w 4 -b 0.0.0.0:5000 app:app --config app/gunicorn_config.py
+CMD gunicorn -w 4 -b 0.0.0.0:5000 app:app --config app/gunicorn_config.py --log-level debug