[devtools] even better: use a plain Connection (server-side) object for pre_setup
The previous commit switched from passing a Session to a
ClientConnection.
This fixes unittest_ldapsource's pre_setup_database, which relied on a
server-side object to get at the repo.
addressbook
basket
blog
book
calendar
comment
company
email
file
folder
i18ncontent
keyword
link
mailinglist
person
tag
timeseries
vcsfile