Notify the server owner about the uProxy server software updates required and enable a seamless upgrade

[ghost]

Currently a server owner has no mechanism to know whenever the uProxy server is outdated. We need a solution that:
a) allows the server to monitor if it's out of date
b) notifies the server owner (e.g. app, email, etc) to take action
c) allows the server owner to upgrade the server (possibly overwriting the droplet / image)
... alternatively, we could consider a server that auto-updates.