py-django-celery-beat: updated to 1.1.1

1.1.1
- Fix interval schedules by providing nowfun.
- Removing code that forced last_run_at to be timezone naive for no reason, made timezone aware. Fixes crontab schedules
- Entry.last_run_at is no-longer timezone naive.
- Use a localized PyTZ timezone object for now() otherwise conversions fail scheduling breaks resulting in constant running of tasks or possibly not running ever.
- Fix endless migrations creation for solar schedules events.
- Prevent MySQL has gone away errors.
- Added support for Django 2.0.
- Adjust CrontabSchedule's minutes, hour & day_of_month fields max length

(adam)