The live CD should somehow prompt for language/country/keymap for blind people

[Samuel thibault]

The graphical boot menu is not accessible to blind users, and thus it's
very difficult for them to choose the language and keymap at that time.
When any accessibility feature is enabled, language and keymap should
be prompted again once the needed accessibility engines are started.
For instance, for someone that is using speech synthesis,

- boot the liveCD
- press F5 (accessibility)
- choose Screen Reader
- really boot the CD

after some time the gnome desktop starts, but it is all in english with
an american keyboard, and it may even be impossible to non-english
people to just find out where to configure that. What should happen
instead is something like:

- boot the liveCD
- press F5 (accessibility)
- choose Screen Reader
- really boot the CD
- accessibility engines start
- user is prompted for the language and keymap
- accessibility engines adapt to the new language (speech synthesis
switches to french for instance)
- a localized gnome desktop starts.