Save the path where Subset Games saves are stored

FTL and Into the Breach under Linux.

Guides/os.md

@@ -30,6 +30,10 @@ Install xfce terminal with **Ubuntu software**.
 
 Use the command : `sudo update-alternatives --config x-terminal-emulator`
 
+### Game save folder for Gog games
+
+FTL and Into the Breach saves are in `.local/share/` folder.
+
 ## Grub
 
 `sudo update-grub`