add "default" option to LDAPReferrals, to allow "off" to really mean "off".

Need compatibility tag/note if backported.

Submitted By: Jan Kaluza & Eric Covener



git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/trunk@1518265 13f79535-47bb-0310-9956-ffa450edef68