[Enhancement] Append /<PLATFORM> to gameListFolder if defined in [<FRONTEND>]

[ASHGOLDOFFICIAL]

To Reproduce

• Define gameListFolder option in some [<FRONTEND>] section.
• Run the scraper.
• It places game list into gameListFolder not gameListFolder/<PLATFORM>

Expected behavior
It should behave the same as when defining gameListFolder in [main] section.

[Gemba]

Let me consider the implications, but right now I thinks it is a good enhancement.

Edit:
@ASHGOLDOFFICIAL On a second thought: What is the use-case / ease-of-use benefit for having this setting with the appended plaform folder in the frontend sections?

[ASHGOLDOFFICIAL]

Use case: for example I use two different frontends (ES-DE on PC, and some other on my handheld emulator console). If that's the case, I need two different configs with different gameListFolder. It would be easy for me to have one config file that I can store on my GitHub. Something like that.

[Gemba]

Thanks for the input. Makes sense.

[Gemba]

As the change would only be valid for ESDE (and Emulationstation and Retrobat) frontend, does the environment variable ESDE_APPDATA_DIR fit your needs already? This environment variable is also evalutated by Skyscraper.