[Feature request] detect iwads from steam

[voidlily]

gzdoom is able to detect iwads automatically based on installed steam games. it would be nice if doomlauncher could do that too.

[kenbot]

Auto detection of IWADs, including DOOM, DOOM2, TNT, Plutonia, Heretic, Hexen, Strife, Doom 64 and all the officially released PWADs like No Rest for the Living, Master Levels, Legacy of Rust, Sigil 1 and Sigil 2 for Steam and GOG will be in the next version