Labels not working when using country code

[Eseperio]

When using country code (en-GB, es-ES, pt-BR...) the labels does not display. Country code is needed for locale number and currency formatters.

A simple solution could be appending the country code at the end of the label.
Ending with something like this:
English GB
English US
Portuguese PT
Portuguese BR

[kmergen]

Please override public static function label().

Please check also if it possible for you to use codemix\localurls\UrlManager to set your languages. you can do it in your config file.

'urlManager' => [
            'class' => 'codemix\localeurls\UrlManager',
            'enableLanguagePersistence' => false,
            'enableLanguageDetection'  => false,
            // List all supported languages here
            // Make sure, you include your app's default language.
            'languages' => ['de', 'en', 'es', 'ru'],
            'enablePrettyUrl' => true,
            'showScriptName' => false,
            'enableStrictParsing' => false,
            'cache' => null,
            'rules' => [
                [
                    'class' => 'yii\rest\UrlRule',
                    'controller' => ['api/v1/hunderasse', 'api/fische'],
                    'pluralize' => false,
//                    'tokens' => [
//                        '{id}' => '<id:\\w+>'
//                    ]
                ],
                '<controller:\w+>/<id:\d+>' => '<controller>/view',
                '<controller:\w+>/<action:\w+>/<id:\d+>' => '<controller>/<action>',
                '<controller:\w+>/<action:\w+>' => '<controller>/<action>',
            ],
        ],