def normalize_keys(locale, key, scope, separator = nil)
      separator ||= I18n.default_separator

      keys = []
      keys.concat normalize_key(locale, separator)
      keys.concat normalize_key(scope, separator)
      keys.concat normalize_key(key, separator)
      keys
    end
def normalize_keys(locale, key, scope, separator = nil)
      separator ||= I18n.default_separator

      keys = []
      keys.concat normalize_key(locale, separator)
      keys.concat normalize_key(scope, separator)
      keys.concat normalize_key(key, separator)
      keys
    end
Merges the given locale, key and scope into a single array of keys.
 Splits keys that contain dots into multiple keys. Makes sure all
 keys are Symbols.