Pull request #199: Bugfix/20220426 several bugfixes

Merge in VECTO/vecto-dev from VECTO/mk_vecto-dev:bugfix/20220426-several-bugfixes to develop

* commit '33c7f648':
  VehicleForm: Corrected Selection of Retarder based on EnginePosition again (E2 also has all retarders available)
  VelocitySpeedGearshiftPreprocessor: Removed try-catch again because error was solved in TransmissionInputRetarder.
  Retarder: Corrected error for TransmissionInputRetarder when Gearbox is diseanged but clutch is closed.
  REESSFileBrowser: Added vbat as extension (in addition to vreess)
  FileBrowser: Updated Screensize
  VehicleForm: Solved Problem of Binding for Tabs of EM and GENSet by setting the BindingContext again
  VehicleForm: Updateing Retarder component in GUI
  VehicleForm.vb: Corrected hiding of GEN-Set Tab in Vehicle Editor (only visible for Serial Hybrids)
  VelocityGearshiftPreprocessor: Throw more useful error message in Preprocessing