Additional Improvements to mathlib for C99 Support

These commits add C99-style math error handling to Open Watcom's mathlib.  Specifically, math errors can now be handled via errno, floating point exceptions, or, as an extension, Watcom's traditional error handling.  These commits will technically "break" traditional error handling in the sense that a developer would need to actively enable Watcom-style floating point exceptions if desired.  However, this breakage is probably needed for C99 compliance.

Also added are the *lrint()* and *remquo()* functions, which were not yet implemented.  These additions leave only one more C99 math function to implement (*nexttoward* is still missing).

The mathlib test programs are now split for small and compact memory models.  The test suite is just too large for these two cases.

Finally, some copyright messages were updated to reflect the fact that they are not Sybase code.