make field class public to access column names

VectoCore/VectoCore/InputData/Reader/ShiftPolygonReader.cs

@@ -106,7 +106,7 @@ namespace TUGraz.VectoCore.InputData.Reader
 					}).ToList();
 		}
 
-		private static class Fields
+		public static class Fields
 		{
 			/// <summary>
 			///		[Nm] torque

VectoCore/VectoCore/Models/SimulationComponent/Data/Gearbox/TransmissionLossMap.cs

@@ -253,7 +253,7 @@ namespace TUGraz.VectoCore.Models.SimulationComponent.Data.Gearbox
 			}
 		}
 
-		private static class Fields
+		public static class Fields
 		{
 			/// <summary>[rpm]</summary>
 			public const string InputSpeed = "Input Speed";