Watarcade 1.7 - Introducing: The Sub

- Added a new single player only game mode: The Sub. Beware, information on this game is limited.
- Added new scrolling messages and hopefully fixed some old ones
- Fixed a bug where if you looked at the settings Wavy Nautigate and then tried going back to the menu, it would start the game.
- Fixed a bug where if you started Flow Connections, that would count as clearing a board.