Locale names differ (Native Gettext)

As locale name differ from system to system (on linux the locale is usually appended by the charset, so de_DE becomes de_DE.utf8), I suggest adding a filter in modules/l10n_improvements/class.wppp_native_gettext.php:

if ( self::isAvailable( 'putenv' ) ) {
			putenv('LC_MESSAGES='.apply_filters('wppp_locale', $locale) );
		}
		//setlocale (LC_ALL, $locale);
		setlocale( LC_MESSAGES, apply_filters('wppp_locale', $locale)  );

setlocale fails if the provided locale does not exactly match one available on the system and therefor native gettext translations fail.

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