More requests for comments

[Mark Valence <kurash@sassafras.com>]

There are two other minor changes I'd like to make.  Please comment.

The LDAP backend currently uses a hostname:port from slapd.conf.  I'd 
like to change this to be an ldap URL.  Also, to facilitate a new 
ldap_back_group routine, I want to add binddn and bindpw directives 
that would provide the DN and password to use when resolving group 
memberships.

The other change is to the backend_group routine, which is used in 
determining access rights (with ACLs and ACIs).  Currently, this 
routine will only work with the backend of the object in question. 
It's fairly simple to change this routine so that objects in a given 
backend can use groups from other backends to grant rights.

Mark.