Allow directory slash in save name when saving

[Dimava]

TL;DR

Make "/" in save name create a directory

What ?

Factorio does support save directories, but you cannot create them from inside the game
Allowing to create them using a slash in directory name would be useful

[FuryoftheStars]

Actually, I'd rather that they didn't do this and instead just put in full, proper support for directories in the dialogs.

Why? Because allowing a slash in the save name is a "hidden" feature that is not obvious to everyone and so you'd still get people asking for the feature.