Remove the AIX work around code. Instead it should just set it's LOCALTIME_MAX to...

Remove the AIX work around code. Instead it should just set it's LOCALTIME_MAX to 0x7fff573e.

Update from y2038.

Use the new TM64 struct so years can go out past y2**31

Defines a Year type to avoid converting years to ints.

Remove the TIMGM work around code, using timegm64() is fine and it
saves us from having to convert from TM to tm.

Make functions private with static rather than the _foo convention.

Even faster for distant dates.