Hints for krb5-auth-dialog in main

Hints

• asv-screenshot-media-url-not-secure
  :102 - http://honk.sigxcpu.org/con/images/krb5-auth-dialog-pkinit.png
  Consider using a secure (HTTPS) URL to reference this screenshot image or video.
• asv-nonstandard-gnome-extension
  :160 - 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-desktop-app-launchable-omitted
  -
  This `desktop-application` component has no `desktop-id` launchable tag, however it contains all the necessary information to display the application. The omission of the launchable entry means that this application can not be launched directly from installers or software centers. If this is intended, this information can be ignored, otherwise it is strongly recommended to add a launchable tag as well.