Fix Binary on python < 2.7.4 (closes #10593811)
Before the fix for http://bugs.python.org/issue10211 we can't pass a
buffer object to BytesIO, so keep using StringIO in that case. And
because StringIO is an old-style class, we can't use super().
addressbook
basket
blog
book
calendar
comment
company
email
file
folder
i18ncontent
keyword
link
mailinglist
person
tag
timeseries
vcsfile