added BatteryHelper to get total usable capacity in simulation

VectoCommon/VectoCommon/InputData/DeclarationInputData.cs

@@ -908,6 +908,14 @@ namespace TUGraz.VectoCommon.InputData
 		TableData MaxCurrentMap { get; }
 	}
 
+	public static class BatteryHelper
+	{
+		public static AmpereSecond TotalUsableCapacityInSimulation(this IBatteryPackDeclarationInputData batteryData)
+		{
+			return batteryData.Capacity;
+		}
+	}
+
 	public interface ISuperCapDeclarationInputData : IREESSPackInputData
 	{
 		Farad Capacity { get; }