Ticket 153 - use openldap's schema parser
    
            Bug Description:  After running ol-schema-migrate.pl(which converts openldap schema to
                              389 DS schema format), 389 still doesn't parse the schema correctly as
                              it expects the syntax to be in a certain order.
    
            Fix Description:  First, instead of only recording the "X-ORIGIN" values, I have created a
                              linked list for all the schema extensions, not just "X-ORIGIN".  Then on
                              systems that have openldap, we use the openldap schema parser.  On
                              systems that only have mozldap, we use the old parser.
    
                              Also did some code cleanup.
    
            https://fedorahosted.org/389/ticket/153
    
            Reviewed by: richm(Thanks!)