A_SYB_NO_COUNT_CHECK configuration variable

When doing a REWRITE, the interface checks to see that a record was actually updated. If the record was not updated, the interface returns an error 23. Setting this variable to ON causes that check not to happen. This improves performance on REWRITE, at the risk of missing an error. While the default value is OFF (FALSE, NO), this configuration variable can also take the value of ON (TRUE, YES).