Merging using //Fortnite/Main/_to_/UE4/Dev-Rendering
#rb none
[FYI] jeansebastien.guay
#ROBOMERGE-SOURCE: CL 8382333 via CL 8382473
#ROBOMERGE-BOT: (v402-8361577)
[CL 8382484 by sebastien hillaire in Main branch]
Added units to the intensity property of point, spot, rect, directional and sky lights.
Refactored the VisualizeHDR so that it shows the HDR view is a PIP on top of the main render.
Fixed PixelInspector results being affected by pre-exposure.
Added a pre-exposure output value to the PixelInspector.
Moved ExposureCompensation to the Exposure tab in post-process settings.
Changed max slider intensity for directional light to be in 120 000 lux
Changed max slider intensity for sky light to be in 50 000 cd/m2
Non bUseInverseSquaredFalloff point lights now have their units forced to ELightUnits::Unitless
Moved light units to advanced display, now that the unit is embeded in the Intensity property
Added Candela, Lux and CandelaPerMeterSquared units to the engine units
Fixed meta data properties to support the "Units" keyword.
#rb brian.karis
#jira UE-64881
#ROBOMERGE-SOURCE: CL 4432979 in //UE4/Release-4.21/...
#ROBOMERGE-BOT: RELEASE (Release-4.21 -> Release-Staging-4.21)
[CL 4432981 by uriel doyon in Staging-4.21 branch]
