StashLogger: Add logToFile option

[Baitinq]

This patch adds the logToFile option in the StashLogger module. This option, which is enabled by default, appends all the newfound stashes to a JSON file ($lambda_folder/stash_logger.json).

This is useful for when you are afk stash hunting and you would like to keep a log of all the found stashes :)

[Avanatiker]

Cool idea, should be saved in a folder named "stash-logger" and have separate files for very server using the brand. Otherwise it would combine indistinguishable the location from different servers.

[Baitinq]

@Avanatiker should be done :)

[P529]

After finding the first stash it doesnt log any other stashes.

Ive set up a small test on a local server, 2 locations with 5+ shulkers each, the first one will get found everytime but the second one doesnt get logged as a stash.

Also, once the first json was created the stash logger didnt seem to create any new json files.

Getting "FileAlreadyExistsException".

Also, I'd suggest adding a new default folder to the FolderUtils for the stash logger if you want this to be a mainline feature. Maybe someone else can chime in if there is something else.