AppStream issues with various XFCE applications

[Richard Hughes]

We've been looking at the AppStream extractor issues in Fedora, and
we've come across a few broken XFCE applications. Broken apps are not
visible in the Ubuntu, Fedora or OpenSUSE application installers. The
apps include:

* xfce4-power-manager
* xfpanel-switch

The full list, along with what failed is available here:
https://dl.fedoraproject.org/pub/alt/screenshots/f26/failed.html --
you can restrict this list to XFCE apps by clicking the [x] button
next to the "XFCE" header.

If you want any suggestions or advice, I'm happy to help. Most of the
failures are pretty self explanatory, e.g. "No <summary> in AppData"
or "icon was too small 32x32" -- our guidelines are here:
https://github.com/hughsie/appstream-glib/blob/master/README.md#guidelines-for-applications

As a reminder, you can validate AppData files using: appstream-util
validate-relax file.appdata.xml

Thanks.

Richard.