UPDATE: In-game option for setting the GIF output directory

Today's update adds an in-game option for setting the GIF output directory. Clicking the "SET" button should open an OS-level folder picker dialog, which seems like exactly the kind of thing that won't work for many people, especially if you're on a more esoteric operating system. If you run into any trouble, email me at zach@zachtronics.com and we can investigate!