Interactive installation with curl | bash

[jedisct1]

Granted, curl | bash feels scary, but things can be done in a sane way, by making the script easy to review, and by allowing a signature to be verified before execution.

All the steps currently required to install a running container could be performed by an interactive script, that:

• Installs Docker if required
• Ask the user about the name of their resolver, the IP address, if they want to enable relayinbg, etc.
• Does everything else automatically. Maybe installing watchtower for automated updates by the way.