Full version: Different difficulties!

Added some code for different difficulties in game, and also made it so you can type exit to close the game
There were also a lot of behind-the-scenes changes, as I rewrote/refactored most of the code!

v0.2

So the last version didn't work if you didn't have swift installed, woops! Here you go, an actual working version

v0.1

This is the first version of the game. I'll try to later add harder modes