Fix high-DPI rendering/input on Windows

[hrydgard]

Turns out this has been broken for a while (well, never working, but since we specified that we were DPI-aware while we really weren't on Windows, things have been wrong).

Also, I'd really like to use modern per-monitor DPI but we can't (without really dirty hacking) as long as we keep XP compatibility, because the XP-compatible Windows SDK only supports up to Windows 7 features, while per-monitor DPI is an 8.1 feature.

Before, on a 4k laptop:

After:

Note the razor sharp text and proper proportions.

[ghost]

Sorry, but WHO! use Windows XP? :)

[hrydgard]

Agree, it's probably time to drop it. But it's a separate issue, most of this work will apply with a modern solution too.

[LunaMoo]

@hrydgard why remove smallWindow condition?:3
Not like I'm using it, but it was making x1 window size usable. If it affects other platforms android with hardware resolution set to x1 ~ which might be popular ~ will also not fit on screen.

Also noticed when there's too many things on the list or the names are too long, things doesn't get wrapped correctly and fly all around window:

but that might be related to some earlier thin3D changes. Edit: oh yeah, wrapping works in d3d backend, so maybe some coords need to be inverted.

[hrydgard]

Woops, that was not intended... I meant to fix smallWindow but forgot to check that it worked, and I obviously didn't get it right.

It will return soon!