Created stats for users (number of users and list of newest users). Better separated the forums, who's online, and user stats. Use a Celery task to execute the new user stats processing. This addresses #194 and #238.

"""
Celery tasks for the POTD app.

"""
from celery.task import task

import potd.tools


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