Ticket 47317 - should set LDAP_OPT_X_SASL_NOCANON to LDAP_OPT_ON by default
    
    Bug Description:  DS should avoid doing DNS reverse lookups for outgoing connections.
    
    Fix Description:  LDAP_OPT_X_SASL_NOCANON is now a configurable option, which is "on"
                      by default.
    
                      Also did code cleanup of slapi_ldap_init_ext()
    
    https://fedorahosted.org/389/ticket/47317
    
    Reviewed by: nhosoi(Thanks!)