Document obj_light

[Moneyl]

Document the behavior of obj_light zone objects. Documentation of properties compatible with obj_light so far is here: https://github.com/Moneyl/RfgTools/blob/main/Documentation/RfgZonexFormat.md#obj_light-inherits-object

[CamoRF]

• Ideal way to test this is probably using pitch black lighting, see Rfg Modding\Pitch Black Lighting\.gtodx & .dtodx on my desktop for those weather/skybox files.