serum powder code

serum powder second ability...
Any time you could mulligan and Serum Powder is in your hand, you may
exile all the cards from your hand, then draw that many cards.

projects/mtg/src/GameObserver.cpp

@@ -1839,6 +1839,13 @@ void GameObserver::Mulligan(Player* player)
     player->takeMulligan();
 }
 
+void GameObserver::serumMulligan(Player* player)
+{
+    if(!player) player = currentPlayer;
+    logAction(player, "mulligan serum powder");
+    player->serumMulligan();
+}
+
 Player* GameObserver::createPlayer(const string& playerMode
                                 #ifdef TESTSUITE
                                 , TestSuiteGame* testgame