Also avoid Comparer allocations

Author: pzgulyas

Source/Orts.Formats.Msts/SignalConfigurationFile.cs

@@ -44,7 +44,7 @@ public class SignalConfigurationFile
         /// <summary>Name-indexed list of available signal functions</summary>
         public IDictionary<string, SignalFunction> SignalFunctions;
         /// <summary>Allocation-free MstsName-indexed list of available signal functions</summary>
-        public static IDictionary<MstsSignalFunction, SignalFunction> MstsSignalFunctions;
+        public static Dictionary<MstsSignalFunction, SignalFunction> MstsSignalFunctions;
         /// <summary>List of OR defined subtypes for Norman signals</summary>
         public IList<string> ORTSNormalSubtypes;
         /// <summary>Name-indexed list of available light textures</summary>
@@ -83,7 +83,7 @@ public SignalConfigurationFile(string filenamewithpath, bool ORTSMode)
             };
 
             // and the allocation-free version of the above 
-            MstsSignalFunctions = new SortedDictionary<MstsSignalFunction, SignalFunction>
+            MstsSignalFunctions = new Dictionary<MstsSignalFunction, SignalFunction>
             {
                 { MstsSignalFunction.NORMAL, SignalFunction.NORMAL },
                 { MstsSignalFunction.DISTANCE, SignalFunction.DISTANCE },