merge from 2.6 branch: use AuthUtils to get group and equivalent identities rather than manually try to extract groups from subject info (can include incorrect groups for given primary subject). https://github.nceas.ucsb.edu/KNB/arctic-data/issues/163
merge from 2.6 branch: use AuthUtils to get group and equivalent identities rather than manually try to extract groups from subject info (can include incorrect groups for given primary subject). https://github.nceas.ucsb.edu/KNB/arctic-data/issues/163