remove docstring indicating that Attachment.properties() is private, since it's required by the interface now.  also, homes don't really have a peruser uid (it's always the regular uid), so don't use that attribute.
remove docstring indicating that Attachment.properties() is private, since it's required by the interface now.  also, homes don't really have a peruser uid (it's always the regular uid), so don't use that attribute.

git-svn-id: 81e381228600e5752b80483efd2b45b26c451ea2@6146 e27351fd-9f3e-4f54-a53b-843176b1656c

trevor/calendarserver,trevor/calendarserver,trevor/calendarserver