def set_locale
  logger.debug "* Accept-Language: #{request.env['HTTP_ACCEPT_LANGUAGE']}"
  I18n.locale = extract_locale_from_accept_language_header
  logger.debug "* Locale set to '#{I18n.locale}'"
end

private

def extract_locale_from_accept_language_header
  request.env['HTTP_ACCEPT_LANGUAGE'].scan(/^[a-z]{2}/).first
end