Fix the starting tail (no idea why it works this way).

snake.go

@@ -14,7 +14,7 @@ func initSnake(snakex int, snakey int) Snake {
 		},
 		tail: []Position{
 			{
-				x: x - 1,
+				x: x - 3,
 				y: y,
 			},
 			{
@@ -22,7 +22,7 @@ func initSnake(snakex int, snakey int) Snake {
 				y: y,
 			},
 			{
-				x: x - 3,
+				x: x - 1,
 				y: y,
 			},
 		},