Random hostname option needed on startup

In advanced options users should have the option to check a box “Random hostname” or “Random computer name” and get a randomly assigned hostname.

Reason being that the “amnesia” hostname Tails currently assigns is a big red flag in certain environments. Some people would prefer to fly under the radar and not call attention to themselves by system administrators.

It could be a simple function where if the box is checked on startup a random number 1-50,000 is assinged as the computers hostname.

Related issues

• Related to #5655

Original created by @redline on 7061 (Redmine)