schema: Add add attributes puavoTimezone, puavoLocale, puavoKeyboardLayout,
puavoKeyboardVariant so that Puavo can be used to configure devices the same
way as normal linux installers do. Keyboard setting still require some
additional parameters that need to be added.
Fix syntax of puavo.ldiff
Merge pull request #4 from opinsys/locale

schema: Add new add attributes for timezone, locale and keyboard settings