added support for {X}{X} in cost, added support for token(creature, X/X or XX/XX)*XX or X or #. added discard card at random as cost type {d}

projects/mtg/src/ActionStack.cpp

@@ -162,6 +162,13 @@ int Spell::computeX(MTGCardInstance * card){
   return x;
 }
 
+int Spell::computeXX(MTGCardInstance * card){
+  ManaCost * c = cost->Diff(card->getManaCost());
+  int xx = c->getCost(Constants::MTG_NB_COLORS)/2;
+  delete c;
+  return xx;
+}
+
 bool Spell::kickerWasPaid(){
   return (payResult == ManaCost::MANA_PAID_WITH_KICKER);
 }