use tmpmemctx for bsi_attrs (should be used more for temporaries)
fix ITS#3480: allow to fetch all attrs or provide hints
fixed access check to entry for rename
TODO: fetch entries for access checking in selected code portions (e.g. rename)
for further mucking with data. This can be of use in ill situations
where not all the required massaging can be done on data with SQL
by means of stored procedures, but overlays are called too early
and cannot be used to make data non LDAP compliant.
- only support for bidirectional DN mucking is provided right now
- support for other values mucking is planned
- write is not completely tested yet
- the API could change quite often; don't rely too much on it
other cleanup has been added.