The autogroup overlay allows automated updates of group memberships which
meet the requirements of any filter contained in the group definition.
The filters are built from LDAP URI-valued attributes. Any time an object
is added/deleted/updated, it is tested for compliance with the filters,
and its membership is accordingly updated. For searches and compares
it behaves like a static group.
If the attribute part of the URI is filled, the group entry is populated
by the values of this attribute in the entries resulting from the search.