sum-data contains wrong output for fuel type (class name of iterator) instead...

sum-data contains wrong output for fuel type (class name of iterator) instead of fuel string. add to testcase

VectoCore/VectoCoreTest/Reports/SumWriterTest.cs

@@ -252,6 +252,8 @@ namespace TUGraz.VectoCore.Tests.Reports
 			Assert.AreEqual(dataProvider.JobInputData.Vehicle.Components.EngineInputData.Model, sumRow[SummaryDataContainer.Fields.ENGINE_MODEL]);
 			Assert.AreEqual(dataProvider.JobInputData.Vehicle.Components.EngineInputData.EngineModes.First().Fuels.First().FuelType.ToXMLFormat(),
 				sumRow[SummaryDataContainer.Fields.ENGINE_FUEL_TYPE]);
+			Assert.AreEqual(dataProvider.JobInputData.Vehicle.Components.EngineInputData.EngineModes.First().Fuels.First().FuelType.ToXMLFormat(),
+				sumRow[SummaryDataContainer.Fields.VEHICLE_FUEL_TYPE]);
 			Assert.AreEqual((dataProvider.JobInputData.Vehicle.Components.EngineInputData.RatedPowerDeclared.ConvertToKiloWatt()),
 				((ConvertedSI)sumRow[SummaryDataContainer.Fields.ENGINE_RATED_POWER]));
 			Assert.AreEqual(dataProvider.JobInputData.Vehicle.Components.EngineInputData.RatedSpeedDeclared.AsRPM,