Fix bad select_related call. In Django 1.8, select_related now throws an error if you give it an invalid field. This was happening. Fix that query. Also noticed an extra query generated in the display_post template. Fixed.

"""
Celery tasks for the POTD app.

"""
from __future__ import absolute_import

from celery import shared_task

import potd.tools


@shared_task
def pick_potd():
    potd.tools.pick_potd()