fix diagonals and user input

src/main.rs

@@ -1,3 +1,4 @@
+use agent::ManualAgent;
 use complexagent::ComplexAgent;
 use game::Game;
 use piece::Piece;
@@ -11,7 +12,8 @@ mod piece;
 
 fn main() {
     let player1 = ComplexAgent::new(Piece::Black);
-    let player2 = ComplexAgent::new(Piece::White);
+    // let player2 = ComplexAgent::new(Piece::White);
+    let player2 = ManualAgent::new(Piece::White);
     let mut game = Game::new(Box::new(player1), Box::new(player2));
     game.game_loop();
 }