Send channel-close-ok in response to server channel-close messages

[foolswood]

This helps around channel reuse in the case of a server initiated close. For instance trying to consume from a non-existent queue. The current handler returns the channel_id to the pool without sending the channel_close_ok. The channel cannot be used (at least with rabbitmq) as the broker is waiting for that response.

[dzen]

Hello,

thank you for bringing us this case. I'll take a look tomorow

[foolswood]

Anything I can do to help on this?

[dzen]

I just need a few times to test it :)

[foolswood]

In my local testing the test I've added fails on master and passes in this branch, hopefully that'll save you some time.

[foolswood]

Is there anything specific you wanted tested?

[foolswood]

We have been running our production system from this branch for a week now, haven't seen any issues with it.

[dzen]

Thanks for your tests and for your periodic notifications !

Do you mind if I ask you to squash your commits and set the commit message like:

channel: send channel-close-ok in response to channel-close ?

[foolswood]

@leth just opening is sufficient. What I wrote does not work on master, but not via a hang, the broker rejects the second channel open request.

[foolswood]

@dzen Are you wanting me to refactor Protocol.channel?

[foolswood]

Rebased

[dzen]

Thank you @foolswood I cherry pick'd your commit and just pushed it to master.