Fix logic for checking whether there is more than one master component in an iCalendar object.
Fix logic for checking whether there is more than one master component in an iCalendar object.

git-svn-id: 81e381228600e5752b80483efd2b45b26c451ea2@2284 e27351fd-9f3e-4f54-a53b-843176b1656c

trevor/calendarserver,trevor/calendarserver,trevor/calendarserver