At least building on Flathub makes presence of this information a hard
requirement now (see <https://blogs.gnome.org/hughsie/2019/03/28/
new-appstream-validation-requirements/> and witness the failed
<https://flathub.org/builds/#/builders/32/builds/3597>).

The suggested way to calculate that information is via the form at
<https://hughsie.github.io/oars/generate.html>, which I filled in as follows
(the answers I selected are prefixed with "=>"):

> By answering all the questions you can generate AppStream-compatible markup
> for the upstream AppData file.
>
> If the user is able to "enable" NSFW or "adult" content, then this should be
> included in the assessment even if it is turned off by default.
>
> What type of component are you generating content for:

=> Application that can connect to the Internet

> OARS has multiple versions, and the newer versions include more questions
> involving specific cultural and religious sensitivities. What version of OARS
> metadata do you want to produce:

=> 1.0 (works with all clients)

> Advertising
>
> Defined as the activity of producing advertisements for commercial products or
> services.
>
> For example, this would include banners showing the Coca-Cola logo shown in a
> Soccer game.

=> None

> Gambling
>
> Defined as taking a risky action in the hope of a desired result.
>
> For example, this would include spinning a wheel to get in-app credits.

=> None

> In-App Purchases
>
> Defined as items or points that a user can buy for use within a virtual world
> to improve a character or enhance the playing experience.

=> None

> Online Text-only Messaging
>
> Defined as any messaging system connected to the Internet.

=> None

> Online Audio and Video Messaging
>
> Defined as any multimedia messaging system connected to the Internet.

=> None

> Contact Details
>
> Defined as sharing identifiable details with other users to allow out-of-band
> communication.

=> None

> Information Sharing
>
> Defined as sharing information with a legal entity typically used for
> advertising or for sending back diagnostic data.
>
> For example, this would include sending your purchasing history to Amazon.

=> None

> Location Sharing
>
> Defined as sharing your physical real-time location.
>
> For example, this would include uploading the GPS co-ordinates of your current
> location. NOTE: This does not include heuristic based location services, e.g.
> GeoIP and others.

=> None

> The following markup can be pasted into the existing application AppData file.
>
> <content_rating type="oars-1.0" />

Change-Id: I063484d8031892c20f88999c5a9beeae3666511c
Reviewed-on: https://gerrit.libreoffice.org/72581
Tested-by: Jenkins
Reviewed-by: Stephan Bergmann <sbergman@redhat.com>