Added additional definition of the Visitor's Browser Language.

Added additional definition of the Visitor's Browser Language. When you visit the site without specifying the language ((/ru/ /en/ /ua/ /de/ /es/ /fr/), the version of the language specified in the browser will be opened. Specify the available language versions on your site to enable automatic redirects. If the language is not found, the main version of the site language specified in the site settings will be opened.