Removes django-background-tasks in favor of Celery.

On staging, everything is started by running ~/start_celery.sh - should
work now for testing.

SciPost_v1/settings/base.py

@@ -80,7 +80,6 @@ INSTALLED_APPS = (
     'django_mathjax',
     'affiliations',
     'ajax_select',
-    'background_task',
     'captcha',
     'colleges',
     'commentaries',

metacore/services.py

 from __future__ import absolute_import, unicode_literals
 import requests
 from .models import Citable, CitableWithDOI, Journal
-from background_task import background
 from rest_framework import serializers
 from mongoengine.python_support import pymongo
 from django.utils import timezone
@@ -10,7 +9,6 @@ from celery import shared_task, current_task
 
 logger = logging.getLogger(__name__)
 
-# @background()
 @shared_task
 def import_journal_full(issn, cursor='*'):
     """
@@ -19,7 +17,6 @@ def import_journal_full(issn, cursor='*'):
     """
     import_journal(issn=issn, cursor=cursor, from_index_date=None)
 
-# @background()
 @shared_task
 def import_journal_incremental(issn, from_index_date, cursor='*'):
     """
@@ -162,7 +159,6 @@ def convert_doi_to_lower_case():
         if i % 1000 == 0:
             print(i)
 
-@background()
 def add_journal_to_existing(journal_issn=None):
     # Take journal from metadata ('container-title') and put it in top-level 'journal' field
     # for all existing citables

requirements.txt

@@ -51,7 +51,6 @@ html2text
 
 # Mongo (Metacore)
 mongoengine==0.15.0
-django-background-tasks==1.1.13
 celery==4.1.1
 django-celery-results==1.0.1
 django-celery-beat==1.1.1