Redesign, Player Name, and ~internet deck~!

This build has the initial Firebase integration. If you add a username, you'll be added to an existing game (sort of). If you close the app and reopen it once you join as a user, you'll see that your hand is the same - that's because it's being pulled from the cloud. So, there might be some weirdness...let me know.

Still working on "real" multiplayer, including how to see who else is playing, and what their face-up cards are. After that, I'll work on "turns", and then after that, I'll add support for the special card that skips the next player (8).

If you have any ideas for how to show who else is playing, let me know!!! I'm currently working on a "sheet" that you can pull up from the bottom that has the list of players registered on the server, but I definitely want to hear from people. I hope the new color scheme is easier on the eyes too 🙄

Fixed: Playing two 7s at once will now properly switch the direction only once, not twice.
Added: License text for the card suit images.

Single-Player with Multi-Select and optional Godmode

Multi-select will be enabled when tapping a card that has a "sibling" card of equal value in the same hand or face-up set. Swipe any selected card up to play all selected cards.
Swiping a single card that has no siblings will also play it without triggering the selection mode, the same as tapping it.
Also adds game-win detection that allows the user to start a new game.

Single-Player Logic

This should cover all the game logic, but only works for a single player right now. Making a release to distribute for testing.