UniqueId and PrimaryGroupId values of 99 are convention for "un set"


git-svn-id: https://svn.calendarserver.org/repository/calendarserver@13529 e27351fd-9f3e-4f54-a53b-843176b1656c
Use latest twext.who


git-svn-id: https://svn.calendarserver.org/repository/calendarserver@13530 e27351fd-9f3e-4f54-a53b-843176b1656c