Add function with tests to remove player from game

Signed-off-by: Sebastian Crane <seabass-labrax@gmx.com>

src/game.clj

@@ -8,3 +8,6 @@
 
 (defn add-player-of-game [state game player]
   (update-in state [:games game] #(conj % player)))
+
+(defn remove-player-of-game [state game player]
+  (update-in state [:games game] #(disj % player)))

test/game_test.clj

@@ -18,3 +18,8 @@
   (is (=
        '#{"player-one" "player-two" "player-four"}
        (get-in (add-player-of-game test-state :quasi-rts "player-one") [:games :quasi-rts]))))
+
+(deftest remove-player-of-game-test
+  (is (=
+       '#{"player-one" "player-three"}
+       (get-in (remove-player-of-game test-state :imaginary-rpg "player-four") [:games :imaginary-rpg]))))