Struct support feature
In VSS-Tools 4.0 structs are supported in the following exporters:
* JSON
* Yaml
* CSV
* Protobuf
Other exporters do not support structs.
It is possible to use specify muliple type files with `--types`, and to use types in combination with overlays.
For more information see [vspec documentation](docs/vspec.md)
Change in UUID handling.
For VSS-Tools 4.0 the following behavior is implemented:
* By default no UUIDs are generated.
* The parameter `--no-uuid` is now considered deprecated, and a warning is given if `--no-uuid` is used.
* No warning is given if neither `--uuid` nor `--no-uuid` is used.
* If both `--uuid` and `--no-uuid` is used an error is given.
Default unit file removed from vss-tools
The default unit file `config.yaml`
has been removed from VSS-tools. This means that either a file `units.yaml` in the same directory as the `*.vspec`
file must exist, or a unit file must be specified by `-u`.
From now on, if new units are needed for the VSS catalog they shall be added to the
[VSS catalog file](https://github.com/COVESA/vehicle_signal_specification/blob/master/spec/units.yaml).