Autosort decks to format folders

The program has format validation functionality for decks already, so would it be possible to have the decks be automatically sorted to format folders that they are legal in?

The format folders would be subfolders of the default deck folder would correspond to the fifteen different formats available to be validated in XMage.
Since .dck files aren't that big, you could have the same deck be in multiple applicable folders until a more elegant solution presents itself.

I don't know if the files could store format validity information in themselves, but if they don't, you could just make a command for the program that tells it to check validation of all decks found in whatever location the user specifies and copying them to the folders accordingly.

No files or tests are named. Start by locating the existing deck format validation and default deck-folder handling, then determine whether sorting or an explicit scan command is the intended scope. Done should define how decks are placed in the fifteen format folders and how decks legal in multiple formats are handled.

Written by the indexing model from the issue text.