d27

The only difference between ordinary and extraordinary is just that little "extra".

Add comment to indicate that study_group.start_date and study_group.end_date is only caching the values

Remove start_date logic from frontend, require at least 1 meeting in API schema and use meetings for start_date and end_date values

Update meeting validation to convert date and time strings to proper Python objects

Filter inline learning circles and applications on the django admin panel to excluded deleted objects

Filter inline learning circles and applications on the django admin panel to excluded deleted objects

Update meeting validation to convert date and time strings to proper Python objects

Merge pull request from p2pu/master Add tasks to anonymize past opt outs