[F&O] IBM-FO-016: Bug in fn:ceiling

(IBM-FO-016) Section 6.4.2, fn:ceiling: Says "If the argument is less than 
zero but greater than or equal to -0.5, then negative zero is returned. 
This seems to be a cut-and-paste error. The value -0.5 doesn't have 
anything to do with the fn:ceiling function.

--Don Chamberlin