* sources/ldap: add forward deletion option
* remove unnecessary `blank=True`
* clarify `validated_by` `help_text`
* add indices to `validated_by`
* factor out `get_identifier` everywhere and `get_attributes`
I don't know what that additional `in` check is for, but I'm not about
to find out.
* add tests for known good user and group
* fixup! add tests for known good user and group
* fixup! add tests for known good user and group
Use the RDN instead of the FDN when establishing group memberships based on posixGroup's 'memberUid' attribute.
fixes#1436
Signed-off-by: Steven Armstrong <steven@armstrong.cc>
