- A locale suggests it is country-specific by having the form <lang>_<country>
- This mostly fixes locale "ar" being presented as "Arabiy (Misr)" when
there is no need to (and the RTL is messed up then, too).
- Introduce intermediate data class for building up the list
of languages to present.
- Sort on the English names, with en_US at the top (ugh).
- Show the native names.
- Much like std::find_if, but slightly muddled because there's
no iterator that we can sensibly use.
- Scan the ComboBox for a locale that matches a predicate.
- Log more as the search for a good locale progresses.
- Don't mix matching the locale with filling the ComboBox
(even though that's slightly more efficient).
In order to avoid deep copies, Qt containers over which we iterate must be const
The remaining unported cases require qAsConst (Qt 5.7) or std::as_const (C++17)
