refactor carryover_info::transfer_all_to

the plan is to fully remove the [side] from [carryover_sides] in this
case, but it needs some testing still.

src/carryover.cpp

@@ -186,22 +186,42 @@ void carryover_info::transfer_from(const team& t, int carryover_gold){
 	carryover_sides_.push_back(carryover(t, carryover_gold, end_level_.carryover_add));
 }
 
+
+struct save_id_equals
+{
+	save_id_equals(std::string val) : value (val) {}
+	bool operator () (carryover& v2)
+	{
+		return value == v2.get_save_id();
+	}
+
+	std::string value;
+};
+
 void carryover_info::transfer_all_to(config& side_cfg){
 	if(side_cfg["save_id"].empty()){
 		side_cfg["save_id"] = side_cfg["id"];
 	}
-	BOOST_FOREACH(carryover& side, carryover_sides_){
-		if(side.get_save_id() == side_cfg["save_id"]){
-			side.transfer_all_gold_to(side_cfg);
-			side.transfer_all_recalls_to(side_cfg);
-			side.transfer_all_recruits_to(side_cfg);
-			return;
-		}
+	std::vector<carryover>::iterator iside = std::find_if(
+		carryover_sides_.begin(), 
+		carryover_sides_.end(), 
+		save_id_equals(side_cfg["save_id"])
+	);
+	if(iside != carryover_sides_.end())
+	{
+		iside->transfer_all_gold_to(side_cfg);
+		iside->transfer_all_recalls_to(side_cfg);
+		iside->transfer_all_recruits_to(side_cfg);
+		//TODO: enable the following line after some testing.
+		//carryover_sides_.erase(iside);
+		return;
 	}
-
-	//if no carryover was found for this side, check if starting gold is defined
-	if(!side_cfg.has_attribute("gold") || side_cfg["gold"].empty()){
-		side_cfg["gold"] = default_gold_qty;
+	else
+	{
+		//if no carryover was found for this side, check if starting gold is defined
+		if(!side_cfg.has_attribute("gold") || side_cfg["gold"].empty()){
+			side_cfg["gold"] = default_gold_qty;
+		}
 	}
 }