Draw fog in the editor

[ActuallyaDeviloper]

Especially volumetric fog is hard to imagine in the editor if it is not shown. We should add an option to draw the fog like in the game.

[MontyTRC89]

Done, for current fog bulb. It's like in the game. No real volumetric fog but just a lerp with gray color based on distance (if you notice on the game, you will see fog only on rendered surfaces).

[ActuallyaDeviloper]

Does this actually still work?

[DustieTRF]

This doesn't seem to work as of version 1.2...