Submission for tic tac toe lab.

What I changed
I completed checkpoints 1-3. I would have submitted all three separately, but a bug prohibited my initial submissions.
I also started working on the nim section of the lab.

Why I changed it
I made these changes in order to make a functions tic tac toe and nim game.

Estimate for remaining time to finish assignment: 15 minutes

nim/player.py

@@ -1,10 +1,10 @@
-from nim.game_stub import NimGameStub
+from nim.game import NimGame
 from strategy.lookahead_strategy import LookaheadStrategy
 
 class HumanNimPlayer:
     def __init__(self, name):
         self.name = name
-        self.game = NimGameStub()
+        self.game = NimGame()
 
     def choose_action(self, state):
         actions = self.game.get_actions(state)
@@ -26,7 +26,7 @@ class HumanNimPlayer:
 class ComputerNimPlayer:
     def __init__(self, name):
         self.name = name
-        self.strategy = LookaheadStrategy(NimGameStub(), max_depth=3, deterministic=False)
+        self.strategy = LookaheadStrategy(NimGame(), max_depth=3, deterministic=False)
 
     def choose_action(self, state):
         action = self.strategy.choose_action(state)