- Made internal include paths relative to src or gen.
  See https://gitlab.eclipse.org/eclipse/simopenpass/openscenario1_engine/-/merge_requests/85#note_1057171)
- Updated all copyrights
- `engine/gen` is now a clean check-in of generated files after 🎄:
  - Moved implemantation of UserDefinedValueCondition to `src`
  - Moved implemantation of VisibilityAction to `src`
  - Generation of LateralDistanceAction cannot handle annotation
    "IsSetDynamicConstrains". The corresponding files have been updated
    manually and then moved to `src`. The generator will not generate
    these files anymore (unless forced).
    See https://gitlab.eclipse.org/eclipse/simopenpass/openscenario1_engine/-/issues/17