Remove use_celery variable
Remove use_celery variable

This project does not come configured with use_celery.
tkjone/wagtail-starter-kit,tkjone/starterkit-wagtail,tkjone/wagtail-starter-kit,tkjone/starterkit-wagtail,tkjone/starterkit-wagtail,tkjone/wagtail-starter-kit,tkjone/starterkit-wagtail,tkjone/wagtail-starter-kit