Trent Mick <trentm@activestate.com>:

Fix PC/msvcrtmodule.c and PC/winreg.c for Win64. Basically:

- sizeof(HKEY) > sizeof(long) on Win64, so use PyLong_FromVoidPtr()
instead of PyInt_FromLong() to return HKEY values on Win64

- Check for string overflow of an arbitrary registry value (I know
that ensuring that a registry value does not overflow 2**31 characters
seems ridiculous but it is *possible*).

Closes SourceForge patch #100517.