Implement error logging and exception catching in FolderBrowser

[ChristosMaragkos]

FolderBrowser uses Directory.GetDirectories to scan the filesystem, which can throw for numerous reasons (path too long, any subdirectory failing, etc.). This is fine but, currently, in the event of an error:

• Nothing is communicated to the user
• The parent directory is not added to the list so the user must click on their filesystem root to get the game back to an interactable state

This PR fixes those issues by:

• Explicitly adding the .. directory to the list if an exception is caught
• Logging all directory errors to the console with Unity's APIs

Closes #2796
Be aware that this does not fix any underlying potential issue. It just clearly communicates any errors to the player.

[ChristosMaragkos]

I also took the liberty of adding a fake directory when an exception is caught to communicate to the user that an error occured in-game. Will revert if too much.

[KABoissonneault]

Did you manage to get any info about your issue from this? Running it should give you the log with the exception now, no?

[ChristosMaragkos]

I wasn't able to because for some reason the game did not fail to scan the directory this time around. Which is a net positive either way.