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* added DashboardStats.queryset_modifiers to allow to modify queryset before it is used in chart, e.g. to add prefetch_related, filters or execute annotation functions. Fixed criteria are now deprecated in favour of queryset_modifiers.
* values in divided chart now are filtered by other criteria choices
* removed support for other JSONFields than Django's native JSONField, removed ADMIN_CHARTS_USE_JSONFIELD setting
* admin charts are loaded by JS including chart controls for quicker admin index load
* --time-until option was added to the `recalculate_charts` management command to recalculate charts only until given date
* CriteriaToStatsM2M.choices_based_on_time_range field changed it's meaning. Now choices are always calculated for whole time range. Value of this choice determines the way how the choices are calculated.