This one was asked for and is pretty reasonable common base
to play with cubox from scratch (being ALT); the intermediate
targets had to be refactored with:

- vm/.cubox-bare becoming *that* bare (it doesn't even
  warrant an init anymore, let alone xorg);
- vm/.cubox-desktop accomodating most of desktop bits;
- vm/.cubox-base becoming vm/.cubox-oem as it should be.

The just-introduced tty feature is employed either.