Fix GroupsCommand


git-svn-id: https://svn.calendarserver.org/repository/calendarserver@13606 e27351fd-9f3e-4f54-a53b-843176b1656c
Break out code a bit more


git-svn-id: https://svn.calendarserver.org/repository/calendarserver@13607 e27351fd-9f3e-4f54-a53b-843176b1656c
Support NOT in recordsMatchingFields across AMP


git-svn-id: https://svn.calendarserver.org/repository/calendarserver@13608 e27351fd-9f3e-4f54-a53b-843176b1656c