I finally got the time to update and merge Mark's and my trunk-math branch. The patch is collaborated work of Mark Dickinson and me. It was mostly done a few months ago. The patch fixes a lot of loose ends and edge cases related to operations with NaN, INF, very small values and complex math.

The patch also adds acosh, asinh, atanh, log1p and copysign to all platforms. Finally it fixes differences between platforms like different results or exceptions for edge cases. Have fun :)

#1629: Renamed Py_Size, Py_Type and Py_Refcnt to Py_SIZE, Py_TYPE and Py_REFCNT. Macros for b/w compatibility are available.

backwards compatibility. Add Py_Refcnt, Py_Type, Py_Size, and
PyVarObject_HEAD_INIT.

Don't pollute the namespace when protecting against multiple header inclusion.
Prefix with Py_ and use standard naming convention Py_FILENAME_H.

Thanks to Skip Montanaro and Kalle Svensson for the patches.

Inhibited complex unary plus optimization when applied to a complex subtype.
Added PyComplex_CheckExact macro.  Some comments and minor code fiddling.