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/include/GameObserver.h

@@ -151,6 +151,7 @@ class GameObserver{
   bool undo();
   bool isLoading(){ return mLoading; };
   void Mulligan(Player* player = NULL);
+  void serumMulligan(Player* player = NULL);
   Player* getPlayer(size_t index) { return players[index];};
   bool isStarted() { return (mLayers!=NULL);};
   RandomGenerator* getRandomGenerator() { return &randomGenerator; };