fdroidserver currently only supports a single WhatsNew field that
comes from the CurrentVersionCode of the app. Google Play and
fastlane supply support a WhatsNew field per-release, but we don't use
that data anywhere, and implementing that in the data structures would
add a lot of complexity since Apk would then need to have its own
"localized" section like App does.
The "Video" field is just a URL pointing to a video.
closes#910
97fd3f0bad