[LDAP] rename unittest ldapuser to ldapsource (prepares #2528116)
the tests involved are not only for ldapuser module but also for the more
general ldapfeed
Necessary to prepare LDAP patch for CWgroup
addressbook
basket
blog
book
calendar
comment
company
email
file
folder
i18ncontent
keyword
link
mailinglist
person
tag
timeseries
vcsfile