Proposal: Returning a message to docker client after powerstrip fails

[aanm]

Powerstrips should return a message to the docker client that made the request informing the request couldn't be completed if one of the adapters fail.
I propose that message to be showed would be a string from the adapter that would be present in ModifiedClientRequest.Body

[binocarlos]

Agreed - a message and a 5xx status code should end up at the docker client. I think we should send the message back in the same format that the normal docker server sends its errors.

ModifiedClientRequest.Body is for normal operations - I think if there is an error, a 500 status and a string that is however the docker server formats its errors - JSON or plaintext?

[aanm]

IMHO since the error is returned in a HTTP form, the error message it should be plainttext