InMemoryChannel Dispatcher Refactor

[nachocano]

Problem
In order to be able to report data plane metrics for the InMemoryChannel, we need to refactor it to use the CloudEvents SDK, instead of MessageDispatcher and MessageReceiver.

Persona:
Which persona is this feature for?
Contributor

Exit Criteria
The InMemoryChannel dispatcher uses the CloudEvents SDK.

[nachocano]

/assign

[nachocano]

/milestone v0.10.0

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Details

In response to this:

/milestone v0.10.0

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[grantr]

/milestone v0.10.0

[n3wscott]

I think this will take more than 1-2 days.

[nachocano]

I think this will take more than 1-2 days.

yeah, removed the bad estimate...