note 11846 added to function.ora-fetch-into.php

I was pulling my hair out this morning. Columns with NULL values were being skipped when I used ora_fetch_into(), which meant my array could have different numbers of elements and different columns in different elements every time! Use ora_fetch_into($cursor, &a, ORA_FETCHINTO_NULLS) to keep the columns rigid. NULL values may not be discernable from empty strings though. I couldn't see this feature anywhere, so I resorted to reading the (excellent) ext/oracle/oracle.c source code. I hope this constant doesn't go away in future versions! http://www.php.net/manual/en/function.ora-fetch-into.php