Add HeatEnergySourcePrototype and FluidEnergySourcePrototype runtime-API

[Therenas]

Currently, LuaEntityPrototypes have their LuaBurnerPrototype or LuaElectricEnergySourcePrototype attached, if those are used. They do however not have anything if they are powered by heat or fluid, which is used in several of the big mods. According to Bilka, this is because there is simply no runtime interface that has been implemented for those, so nothing can be attached. I'm asking for them to be added to the runtime API.

My use case for this is mainly Factory Planner, where I'd like to calculate how much heat or fluid a machine needs to run. I can already do this for 'item'-fuel and electricity, but not for the other two power sources. (The same goes for boiler recipes and the like).

[Deadlock989]

I would also have a use for VoidEnergySourcePrototype or similar. Essentially I want to use on_selected_entity_changed to display custom chunk-based radius visualisations for entities which meet certain emissions criteria, regardless of their energy source type. You can currently finesse this for electric and burner types but it is possible to have void, fluid and I'm guessing heat energy sources that produce or negate pollution as well.

[Rseding91]

Ok, I've added all 3 of those for the next release.

[Deadlock989]

Many thanks.

[Therenas]

Amazing, thank you!