NES: internal debugging infrastructure. when compiled in debug mode, throw if two boards both respond to configure. (in release mode, we short circuit there for speedup). also fix zeromus's fat fingers from r2011

BizHawk.Emulation.Cores/Consoles/Nintendo/NES/BoardSystem.cs

@@ -449,6 +449,7 @@ namespace BizHawk.Emulation.Cores.Nintendo.NES
 		{
 			NES nes = new NES();
 			nes.cart = cart;
+			Type ret = null;
 			lock(INESBoardImplementors)
 				foreach (var type in INESBoardImplementors)
 				{
@@ -464,11 +465,18 @@ namespace BizHawk.Emulation.Cores.Nintendo.NES
 						board.InitialRegisterValues = properties;
 						if (board.Configure(origin))
 						{
+#if DEBUG
+							if (ret != null)
+								throw new Exception(string.Format("Boards {0} and {1} both responded to Configure!", ret, type));
+							else
+								ret = type;
+#else
 							return type;
+#endif
 						}
 					}
 				}
-			return null;
+			return ret;
 		}
 
 		/// <summary>

BizHawk.Emulation.Cores/Consoles/Nintendo/NES/Boards/Mapper078.cs

@@ -16,7 +16,7 @@ namespace BizHawk.Emulation.Cores.Nintendo.NES
 
 			switch (Cart.board_type)
 			{
-				case "MAPPER079":
+				case "MAPPER078":
 					break;
 				case "IREM-HOLYDIVER":
 					holydiver = true;