Add Bridzik.get_player_cards and make get_status player-agnostic

Engine support for the per-connection Socket.IO API: hands are fetched
explicitly via get_player_cards(player) and the shared status no longer
embeds a single player's cards.

bridzik.py

@@ -99,13 +99,16 @@ class Bridzik():
             raise BridzikException('Hra je ukoncena.')
         self.series[-1].add_player_guess(player, guess)
 
-    def get_status(self, player: int):
+    def get_player_cards(self, player: int):
+        player_cards = self.series[-1].get_last_round().player_cards[player]
+        return {k: v for k, v in enumerate(player_cards)}
+
+    def get_status(self):
         status = {}
         last_series = self.series[-1]
         if not self.is_completed():
             status['active_player'] = last_series.get_last_round().get_active_player()
             status['active_round_guesses'] = last_series.get_last_round().guesses
-            status['player_cards'] = last_series.get_last_round().player_cards[player]
             if last_series.get_last_round().is_guessing_completed():
                 status['active_round_stashes'] = last_series.get_last_round().get_stashes_winner_summary()
                 status['active_stash'] = {
@@ -308,7 +311,7 @@ class Round():
             self.stashes.append(Stash(self.get_last_stash().get_winner()))
 
 
-class Stash():
+class Stash:
     def __init__(self, first_player: int):
         if first_player not in [0, 1, 2, 3]:
             raise BridzikException('Cislo hraca musi byt 0, 1, 2 alebo 3.')