#28 Add DIU ID and display on status screen

An ID for each DIU should be created and put in an accessible location. One possibility is the `config` directory with a name like `popufare.id`, with the contents being a unique identifier for the DIU. This could be taken as the `hostname` for the unit or some other identifier. The status screen (before login, after bootup) should display the ID of the unit. | | | |---|---| | priority | low | | estimate | 2 work units |