Version 0.4

• MAIN FEATURE: Version 0.3 had unfortunate behavior where, if you had any extended MSU pack, the shuffler would select all boss-specific and dungeon-specific tracks from a random extended MSU pack, which prevented you from hearing boss/dungeon music from any non-extended MSU pack. Version 0.4 fixes this by first choosing an MSU pack at random, then picking the extended MSU track if it's available, otherwise falling back to the non-extended equivalent. Thanks Logic/miketrethewey for the pull request (sorry it's so late)
• Will no longer recursively delete old MSU packs (only deletes "shuffled-*.pcm, output.log, and shuffled.sfc from the current directory) (sorry again Falcon)
• Added an empty shuffled.msu file since why ask users to do what git can do easily
• Script will now rename any .sfc file in the directory to shuffled.sfc, cutting out an additional unnecessary step
• Added hardlink support to improve speed/cut disk usage (thanks dewin for the suggestion)
• Added --debug in case you want to see what the script will be moving/copying/deleting without it actually doing it (thanks miketrethewey for the idea)
• Prettier output (makes it easier to see what track ended up as what at a glance)