Hints for file-roller in main

Hints

• metainfo-validation-hint
  Validation of the metainfo file yielded the following hint: Found invalid tag: 'kudos'. This tag is a GNOME-specific extension to AppStream and is not supported by all implementations.
• metainfo-validation-hint
  Validation of the metainfo file yielded the following hint: The component summary should not end with a "." [Отваряне, създаване и промяна на архиви и компресирани файлове.]