- acos() now returns 0 for a domain error.
- asin() now returns 0 for a domain error.
- atan2() now returns 0 for a domain error.
- fmod() now returns x if y == 0 and sets a
domain error.
- sqrt() now returns 0 for a domain error.
- Added NaN and +Inf constants to the math library
initialization code which could come in handy later.
