Added Docker node-red admin command access

[MaxVRAM]

Just a documentation addition and slight formatting adjustments for clarity.

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[jsf-clabot]

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[MaxVRAM]

Solving #193

[dceejay]

thanks - looking at the README there is already a section around line 372 about node red admin... which is probably where this should fit. The intention of that section was installing node-red-admin outside of the container and updating the shared volume - but would be useful if it also covered doing it inside the container as you want.

[MaxVRAM]

@dceejay I see. I don't think I saw that section when I was first going through the docs. Either way, you're right, there's still a use-case for this. I've popped it under the existing admin section and fixed formatting/wording to be more consistent with the context. As a bonus, I think it flows well into accessing bash into the container.

[dceejay]

great - many thanks