Enhancement: allow sparks to emit (rt) light in a small area

[spiro9-peef]

What would this enhancement be for?

Rendering

Describe your enhancement suggestion in more detail

Currently, sparks do not have any light emission. This was fine, seeing as rt lighting wasn't implemented yet. However, now that rt lighting is here, I believe that sparks would benefit from having small-radius lighting emission as a toggleable option.

I am aware that this may not be possible since, to my knowledge, the sparks of env_spark are just particles. But if there is a way to enable them to emit light I would be very eager to see it!