* Moved Slate.h into SlateBasics.h and began shifting less commonly used headers into SlateExtras.h.
* Slate.h now simply includes SlateBasics.h and SlateExtras.h.
* Slate.h includes a deprecated warning now to indicate that SlateBasics.h + specific includes should be used instead.
* Moved dozens of inlined functions using Slate widgets into .cpp files to avoid header dependencies.
* All code samples now include SlateBasics.h and SlateExtras.h so future shifts will not break most those projects, but not trigger the deprecation warning of including Slate.h.
#BUN
[CL 2329610 by Wes Hunt in Main branch]
#ttp 318670 - UE4: RENDERING: FORTNITE: Write HighResScreenshots to OpenEXR (ideally PSD as well)
#proj Engine
#branch UE4
#summary Added OpenEXR library, added OpenEXR format to ImageWrapper Module, Changed highres screenshot code to save with image wrapper.
#Add OpenEXR support (for writing) to ImageWrapper module. (enabled for windows builds only)
#Add added option to highres screenshot code to choose to output as hdr / openexr
#Add 2 new visualisation modes, scene depth world units and custom depth world units.
#add cvar 'r.BufferVisualizationDumpFramesAsHDR' to enable hdr export from console.
#change FRCPassPostProcessMaterial can specify an override output texture format if required.
#add SaveImage function to FHighResScreenshotConfig
[CL 2252882 by Allan Bentham in Main branch]
Several other fixes for high res screenshot issues.
Default behaviour of screenshots with viewport-locked cameras is to only capture the actual viewrect, not including the black bars. Removed button for setting capture region to view rect.
[CL 2235681 by Graeme Thornton in Main branch]