Mod reloading at "runtime"

[y.petremann]

Actually when we have multiple mods configurations, it's hard to manage them.
My idea is that when we load a world it, if the current mod configuration is different from world mod configuration, it would ask us if we want to update mods mod configuration.
If yes, the it would start the game directly like now
If no, the game would configure itself to the world mod configuration, restart itself and launching directly the world.

For that we also need that factorio could start with multiple version of a mod availlable