linuxlive 0.2.0: an installer

Every Ubuntu-based ISO can now install itself: an Install icon on the live desktop and an Install boot-menu entry open a small installer (disk, name, user, password, computer name, time zone, log in automatically). After you type erase it erases that whole disk and installs the system, booting under UEFI with Secure Boot (through Ubuntu's signed shim) and under BIOS. Casper, the live user and upstream's first-login wizard are left out.

CI installs both Ubuntu examples unattended in QEMU and boots the installed disks to the desktop (UEFI with Secure Boot) and under BIOS; verify-results has a new install check. Proven by run 38463987701.

Not yet: dual boot, encryption, and an installer for Fedora-based ISOs. To use it, change @v0.1.3 to @v0.2.0 in your workflow.