Implement a clean update mechanism

[debloper]

This utility is meant to be "set it and forget it", so no one is forced to update if they're satisfied with how it's working for them. It shouldn't even have to have automated updates, notifying annoying them to update.

But at least for the ones who want to stay at the bleeding edge & update, it shouldn't be more than just one or two scripts to run.

[andiohn]

Perhaps on reboot it can add a 'update me' page to the urls it cycles through? Then you log in to the admin portal and push go.

[debloper]

Yes, there are 3 parts to this:

• check if update is available (compare local vs upstream git tree)
• show the call to action UX when update is available
• run update script & reboot to apply changes