Merge pull request #824 in VECTO/vecto-sim from...

Merge pull request #824 in VECTO/vecto-sim from ~EMQUARIMA/vecto-sim:ReleaseCandidates/v3.3.6.1898 to master

* commit '9f55d21e':
  fix bug in creating new gearbox file for AT-S from scratch. GUI tries to use vehicle category in order to decide whether TC is used in 1st or 1st and 2nd gear. use 'not truck' as default