Code review comment for ~waveform/ubiquity:prepare-package

The pi images use (and have always used) oem-config for the initial user setup (and language, timezone, keyboard, etc). The only bit that gnome-initial-setup takes care of is the greeter after the (freshly created) user first logs in.

Incidentally, I've now discussed the requirements of the pi desktop with the installer team; while support for pre-installed images is planned this cycle, it is unlikely that the specific pi case will be supported this cycle (it'd be "nice to have", but I take that as "unlikely"). So, given we'll likely have oem-config again this cycle, I'd really like to get this merged so I can build test images cleanly.