Directory for saved files not created automatically

[mankrip]

Hi, thanks for bringing updates to this port.

I installed prBoom in my New 3DS a while ago, but was never able to play it because the game would fail to save my options and would also fail to create savegames.

Now I noticed that when quitting the game, a message saying that it was unable to save the configuration file in the 3DS/prboom3DS directory is displayed. So I opened the FBI app, saw that there was no prboom3DS directory in the 3DS directory, and created it manually. Now the game can create and save all files normally.

A fix for this issue in the engine itself is to check if the prboom3DS directory exists upon launching the game, and if it doesn't, the engine should automatically create it.

[Wavy667]

Major apologies for coming back to you 5 whole months since you opened your issue (I barely check my GitHub repos), but I guess it's better later than never.

Anyways, a fix for this should be super easy so I'll get it done some time soon.