adding aggregator field as it is used for measure calculation
adding aggregator field as it is used for measure calculation

Xodarap/health-data-standards,okeefm/health-data-standards,Xodarap/health-data-standards,PheMA/health-data-standards,okeefm/health-data-standards,thecristen/health-data-standards,projectcypress/health-data-standards,thecristen/health-data-standards,projectcypress/health-data-standards,PheMA/health-data-standards