Setting locales with region or script doesn't work due to case sensitive locale tag comparison

[daniel-micic]

Setting locales like zh-Hans or pt-BR doesn't work because of case sensitive comparison in resolveLocale(locale) in Tolgee class.
Locale tags fetched from cachedManifest from Tolgee backend are strings like "zh-Hans", "pt-BR" etc. But generateLocaleFallbacks(locale) function generates tags "zh-hans", "pt-br" which causes the condition if (candidate in availableLocales) on line 244 to wrongly result in false since contains() is case sensitive