Only write changes back out if something changed
Only write changes back out if something changed

Adding a goal does one database update per enrollment the user is in,
this way at least these writes are only done if the contents has
actually changed.

robertobarreda/django-experiments,squamous/django-experiments,squamous/django-experiments,mixcloud/django-experiments,robertobarreda/django-experiments,bjarnoldus/django-experiments,mixcloud/django-experiments,squamous/django-experiments,uhuramedia/django-experiments,mixcloud/django-experiments,bjarnoldus/django-experiments,robertobarreda/django-experiments,bjarnoldus/django-experiments,uhuramedia/django-experiments,uhuramedia/django-experiments