Update `cli_printMessage' functionality:
    
        - Add `--as-template-line' option.
    
    Update `render' functionality:
    
        - Move DOCTYPE verification from `render_doTranslation' to
          `render_doBaseActions'.
    
        - Start using `--as-template-line'.
    
        - Rename TEMPLATE_DOCTYPE variable to TEMPLATE_HAS_DOCTYPE.
    
        - Perform document validation, only if it has DOCTYPE definition
          set inside.
    
        - Print translation line only when translation files do exist.
          Otherwise, weh translation files don't exist, don't print
          translation line to save vertical space.