HybridStrategy: FindBestGearForBraking: added check if targetSpeed is actually 0 when checking for DisengageWhenHaltingSpeed. Otherwise braking below 10 km/h caused problems, because gearbox disengaged.

AbstractSimulationDataAdapter.SetCommonRetarderData: moved access to ratio back to the place when we are sure that the retarder exists.

RetarderTest: Added additional test for creation of different retarder types and powertrainPositions

JSONRetarderInputData: Removed check if retarder is allowed. Now it just reads the retarder, if it is defined in the file.

handle the case that in the first simulation interval (if the vehicle does not start from standstill) no sulution is available
aa