Handle LDAP search references
    
    LDAP search operation may return a search reference pointing to
    an LDAP resource. As the framework does not handle search
    references, skip these results to prevent result processing
    failures.
    
    Migrate operation crashed when the migrated DS contained search
    references. Now, it correctly skips these records and prints the
    failed references to user.
    
    https://fedorahosted.org/freeipa/ticket/1209