Fix Dockerfile

Dockerfile

@@ -2,6 +2,7 @@ FROM python:3
 ENV PYTHONUNBUFFERED 1
 RUN mkdir /django
 ADD ./comet /django/
+ADD ./requirements.txt /django/requirements.txt
 WORKDIR /django
 RUN pip install -r requirements.txt
 CMD sleep 5; python manage.py migrate; python manage.py collectstatic --noinput; gunicorn comet.wsgi -b 0.0.0.0:8000