add the option to reinstall a specific component

[pellcorp]

So for instance --reinstall nginx if the second argument is a recognised component we will forcefully reinstall that component, and the components would be:

• klipper
• moonraker
• nginx
• fluidd
• mainsail
• crowsnest

I don't think we should support things like probe stuff, this is just to force the reinstall of main components for convenience

this is a low priority