Create a "ReShade" extension to cater for all shader mods

[IDCs]

ReShade is very popular for UE5 games - rather than have the game extensions themselves provide installers and modTypes to install these mods, we might as well create a core extension which caters for these types of mods for all games.

[Pickysaurus]

ReShade is for every game really, not just UE5. However, the problem is that ReShade files tend to not have any consistency in the names. We'd need to parse the INIs or shaders and work out if they're intended for ReShade.