def reload(file = nil)
      clear_all
      if file
        read file
        return true
      end
      read_global
      read_user
      return true
    end
def reload(file = nil)
      clear_all
      if file
        read file
        return true
      end
      read_global
      read_user
      return true
    end
Clear the settings and reload the prefs files, or another file if provided

 @param file[String,Pathname] a non-standard prefs file to load

 @return [void]