change the policy wrt $ sudo docker to simplify auto-testing

so long as its ``$ sudo docker`` i hope its still easily copy&pasteable

we also need to work out how to differentiate between the docker host prompt and a container's prompt, but I'm sure that the sphinx plugin work (when it gets done) will inform us as to the details :)

What i'm wanting to do, is to make a sphinx plugin that will see commands, and execute them, and then compare the output to that in the doc - optionally, it could update the doc, and then let us review and commit the update.

(I'm bothered by the difficulty in making sure that the examples are still correct - or even correct the first time - it seems too easy to miss one of the 12 parameters)

@metalivedev @kencochrane @jamtur01 
 
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