documentation: Describe the state machine

[jkczyz]

The state machine is mentioned but isn't well defined. Give a brief description where it is introduced.

[arik-so]

Where do you think this description is most aptly placed?

[jkczyz]

Probably in README.md under "Channel Management" where the term is first used. Just needs a little clarification because, as stated, "the state machine" leaves a lot to the imagination. What's state? What causes state transitions?

It may sufficient to rephrase the entire sentence if the remaining responsibilities in the list are related to the state machine management. That is, define the state machine in terms of these instead.