This commit will break your current `kotnetcli`. Just use one of the releases for a working `kotnetcli`.

I've started re-structuring the code.
- each Communicator is aware of the action that the worker is going to perform (`uit_te_voeren_procedure`)
- `beeindig_sessie` will show the end status as well, because there's really no need to put it in a separate method like `eventSamenvattingGeven`