Add support for controller-specific Serial API commands (e.g. through plugins)

[AlCalzone]

Some controllers, e.g. Aeotec Z-Stick Gen5 bring their own serial API commands which use proprietary function types. We could add support for them and auto-load the correct controller "plugin" after the controller was identified.

See the document in https://github.com/zwave-js/node-zwave-js/discussions/1241#discussioncomment-237385 for a description of the commands.

Discoverability of these commands for developers is an issue though.