Dead since 919fa12, ie. v0.0.4

Having just 4 valid actions (albeit they do form a meaningful workflow)
was rather historical limitation caused by author's negligence.
User should be able to define any actions they want by simply creating
handlers for them.

Later we might want to provide a guidance (template) for that, but
that's a TODO item.

The host split turned to be a vast overengineering.