Kodi Windows HDR 1.7.2

Updated at 06-01-2020 (forked from Kodi 19 alpha master).

Eliminate rounding errors when handling HDR metadata.
Updated with latest master branch commits.

To use HDR features enable Windows HDR switch before open Kodi or toggle HDR ON from power options menu in Kodi.
If video has HDR metadata enables proper rendering.
Can also play SDR content with Windows HDR switch ON and it is displayed correctly.
And HDR content played with Windows HDR switch OFF is displayed correctly too (with no HDR).
Uses Microsoft Windows standard API to HDR passthrough.
If Windows HDR switch is turned OFF, it behaves like the normal Kodi edition.
For devices without HDR display capable uses HW tone mapping (DXVA) or SW tone mapping (pixel shaders) for HDR to SDR conversion.

Tested on Intel NUC 8i3BEK + Dennon AVX-1600H + Sony TV KD-55AG9 OLED.

Also works on NVIDIA / AMD hardware.