[PATCH] ucrtbase: Implement t and j printf length modifiers.

[Ambrož Bizjak]

Hi,
This adds support for t (ptrdiff_t) and j (intmax_t/uintmax_t) length
modifiers. This fixes an issue in Planet Coaster where many in-game
values would otherwise show as "jd". I've confirmed the fix works
within Steam Play with a local Proton build.

These length modifiers have appeared in VS2015 together with z, so
putting the code under "_MSVCR_VER >= 140" seems correct. Tests are
included and they passed for me on 32-bit and 64-bit.

Regards,
Ambroz Bizjak