LOBStreamControl shouldn't throw SQLException

LOBStreamControl throws three types of exceptions: IOException, SQLException and StandardException.
All the SQLException are generated/thrown from the code in LOBStreamControl.
At this level of the code, SQLException should not be thrown, as it is more tedious to handle both SQLException and StandardException at higher levels.

I propose to replace SQLException with StandardException in LOBStreamControl. The purpose of this change is consistency, and also results it slightly less code at higher levels.