Hints for sayonara in main

Hints

• asv-cid-contains-hyphen
  :4 - com.sayonara-player.Sayonara
  The component ID contains a hyphen/minus. Using a hyphen is strongly discouraged, to improve interoperability with other tools such as D-Bus. A good option is to replace any hyphens with underscores (`_`).
• asv-nonstandard-gnome-extension
  :38 - kudos
  This tag is a GNOME-specific extension to AppStream and not part of the official specification. Do not expect it to work in all implementations and in all software centers.
• asv-content-rating-missing
  -
  This component has no `content_rating` tag to provide age rating information. You can generate the tag data online by answering a few questions at https://hughsie.github.io/oars/