0005597: Language setting by URL ?lang= parameter ignored for multilang ...

...environments with multiple non-ssl domains and single SSL domain.

Domain name took precedence over &lang= parameter; in multi-shop environments, this resulted in the inability to use a single SSL domain with multiple non-SSL domains: during checkout, upon redirecting to the SSL domain, the shop would switch back to the first language using the SSL domain.

An additional check in oxLang::getBaseLanguage() fixed this.